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[1.12.5] Bluedog Design Bureau - Stockalike Saturn, Apollo, and more! (v1.14.0 "металл" 30/Sep/2024)


CobaltWolf

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45 minutes ago, blowfish said:

http://heroicrelics.org/info/titan-i/titan-i-stage-2-engine.html

  Reveal hidden contents

 

I've generally found Heroic Relics to be a reliable source

HA I had totally forgotten about that data!   I even have a book mark in my browser for it!   It was in my "KSP mods" folder instead of "KSP data"   DOH!   Thanks for the reminder Blowfish!    So per Heroicrelics, the main "Sustainer" engine is activated 4 seconds after separation.   Given 1st stage is till spooling down and providing thrust  of various levels that would mean we are still dealing with a "Fire in the hole" ignition but the stages are actually separate.    That actually makes the comments about "jet-wash creating force differentials on the interstage structure causing it to deform,"  still make sense.  That is the Coanda effect I was talking about in the post (sorry if I am spelling that wrong.)   I guess  that means my Titan I launches are going to have a fuel  sensor on Stage 1 and a pair of timers on stage 2.   Set the fuel sensor to 2-3% (unsure will take some experimentation,) and then the action group it activates starts a 7 second timer on the 2nd stage and activates the vernier engines on the LR91.....     Then the first timer will trigger stage separation and for good measure First stage main engine shutdown, and a 2nd timer for 4 seconds.   The second timer then activates the main LR91 thrust chamber after those four seconds. I will edit my post to bring these details in and make it clearer.     

 

To sum up the LR91 DOES use fire in the hole on the Titan I.   But it does so just after stage separation and not while the two stages are attached.     It is too bad there isn't a better way to do this.   The Smart Parts mod is already in my mod circulation but each of those parts will cause issues with 1.11 (no I am not going to hack my physics.cfg to "fix" the problem!)   This is me staying on 1.10.1 :D

 

Thanks again for helping me make the document a little better @blowfish!    I really appreciate it.        Also thanks for pointing out that I should point settings/other mods out for the various rockets to make the builds more realistic in KSP.   I use the SmartParts fuel drain detector on many Titan rockets (any that has a SRM/SRMU on it for certain!)   You didn't say it in words, but your posts lead me to that decision/conclusion.

 

Now how to word this in the document.........

 

I will edit the Titan I document tomorrow after work or maybe on Thursday (the start of my normal weekend.)    This is my first week back to work after Covid and I am having issues getting to sleep at a "good" time.  

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13 hours ago, KeaKaka said:

I think this is a bug, an Atlas V in the 401 configuration cannot provide enough thrust for it to leave the pad, it only has a TWR of 0.83.

Just for reference, in 1.10.1 a freshly constructed 401 configuration with no payload shows:  stage 1) 1.19/4665m/s,  stage 2) 0.47(vac)/5994m/s, with a Isor in 10C1 mode.

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5 hours ago, Pi_Maaster1337 said:

Does it support realism overhaul?

The question you should be asking is does RO support this.

I don't know the exact state of everything right now but in general BDB changes fast enough that the RO configs are often out of date.

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Asking about things outside of your understanding is always fun ... so here I go!

Would it be possible to copy the Lead Ballast resource config from the Prometheus-II nosecone into the S-IVB Lander Adapter Module?

If that's the dumbest thing you've ever heard, sorry but here's my rationale. I need a mass simulator for Apollo 8 and I have no ore tanks unlocked. At first I was looking for parts ... parts that add weight but don't add any other modules that would affect the vehicle. The nosecone has the weight but also has a probe core and reaction wheels that need to be turned off. Plus it's a part and I don't need a part I just need the (optional) weight. Thus the idea of just copying the resource and making the LAM have a "with or without LM" type of setting.

Just to show more stuff I don't really understand ... I figured out the 700 lead ballast number I needed for the nosecone to simulate the LM by building the LM, noting the wet mass of 8t, then starting a new build with just the nosecone, and tweaking until its mass was 8t. But the number "700" (after setting other stuff to 0) seems pretty arbitrary to me. Is there a resource type where 1 unit = 1 ton so I can just set a slider to 8 or 8.1 and not have to guess ? Umm, like a weight resource? ok sorry i'll just be over here

 

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2 minutes ago, OrbitalManeuvers said:

Asking about things outside of your understanding is always fun ... so here I go!

Would it be possible to copy the Lead Ballast resource config from the Prometheus-II nosecone into the S-IVB Lander Adapter Module?

If that's the dumbest thing you've ever heard, sorry but here's my rationale. I need a mass simulator for Apollo 8 and I have no ore tanks unlocked. At first I was looking for parts ... parts that add weight but don't add any other modules that would affect the vehicle. The nosecone has the weight but also has a probe core and reaction wheels that need to be turned off. Plus it's a part and I don't need a part I just need the (optional) weight. Thus the idea of just copying the resource and making the LAM have a "with or without LM" type of setting.

Just to show more stuff I don't really understand ... I figured out the 700 lead ballast number I needed for the nosecone to simulate the LM by building the LM, noting the wet mass of 8t, then starting a new build with just the nosecone, and tweaking until its mass was 8t. But the number "700" (after setting other stuff to 0) seems pretty arbitrary to me. Is there a resource type where 1 unit = 1 ton so I can just set a slider to 8 or 8.1 and not have to guess ? Umm, like a weight resource? ok sorry i'll just be over here

 

Interesting question.   I personally perfer using a part like the old NRAP or the new "adjustable ballast" that I have seen on spacedock.  Let me see if I can point you to the mods.

NRAP is unlock-able at the start of the tree so you can use it right from the word go.

I strongly STRONGLY do not suggest modifying core BDB parts to "add a mass simulator"    This can go wrong in so many ways....    Creating a duplicate part that has a mass simulator is the better choice (using a MM patch with the +PART option!)

https://spacedock.info/mod/386/Kerbal NRAP - Procedural Test Weights

https://spacedock.info/mod/2265/Utility Weight

 

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5 minutes ago, OrbitalManeuvers said:

Thanks for the links. The nosecone works fine if I want to go the part route - I definitely do not need to be adding more mods for this one use case.

I actually use NRAP to test ALL my rockets when I am building custom payloads.  

It comes in various sizes and you can adjust the masses.   NRAP is what gave me the idea to convert the old Titan I Mk4 reentry vehicle into a DMAGIC impact science experiment (it didn't work out too well however and now the MK4 RV is gone...!)

 

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1 hour ago, OrbitalManeuvers said:

Is there a resource type where 1 unit = 1 ton so I can just set a slider to 8 or 8.1 and not have to guess ? Umm, like a weight resource?

Water weighs 1kg, so 1000 water = 1 ton. I believe it's been used in the real world as a mass simulator. Our cargo parts should be already setup to carry it too.

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Ok so I have not begun to edit my Titan I post on the previous page yet.   But I wanted to give you a build guide using SmartParts mod and BDB to automate and give you a CORRECT Stage 1 and Stage 2 separation.   And with the same concept you can fully automate your launch (with Mechjeb) all the way to orbit.... with more accurate and realistic staging than MechJeb alone can provide.

 

1st)   as I said I am using the Smart Parts mod:

https://spacedock.info/mod/614/SmartParts

On the 0 stage (if you are running SRMs)   Put Two un-related Fuel sensors.   Set one to 4 Percent.... have it either stage or activate the 1st Stage LR87-AJ-3 engine.      The second fuel sensor, have it set to 0 and set it to either stage or eject your SRMs.     I tend to run Aerojet AJ100 SRMs on Titan I (called SOLTAN in BDB.)

Add a single fuel drain sensor on Stage 1.    Set this to 7%.    Set it to Activate an Action Group.     In whatever action group you choose you will need the following.    The "Activate Engine" that is at the BOTTOM of the LR91-AJ-3 (there are 2 activate engine buttons on the LR91!)   and start a 7 second timer (from Smart Parts.)  The timer MUST BE on the 2nd stage!  

Spoiler

6% fuel will give you APROXIMATELY 6.8seconds of fuel...   So setting the 1st stage Drain sensor to 7% DOES reduce your total ISP by a few seconds.   But this is more realistic to the Titan I flight profile.   The First stage was flown to MECO not to Fuel starvation!

The 7 second timer will activate another Action group.   In this 2nd (or more depending on how YOU build your Titan I) you will put another timer (set to 4 seconds this time!)  and you will Stage the Stage 1 to stage 2 interstage.    Please note the First stage engine will be running out of fuel AFTER this action if you set it to 7% above.   So I also shut down the 1st stage main engine at this time.

Next you will add a 2nd Timer to the 2nd stage set to 4 seconds.    This timer must be activated by the  first, 7 second timer you installed above!

The 4 second timer will activate  The UPPER LR91-AJ-3 "Activate engine" as it's only action.    Again this is an Action Group.

After the 2nd timer has expired and performed it's actions you will have a properly staged Titan I.

Spoiler

Please note I did 3 test flights with this basic setup (and a more advanced version)   I flew them at 6% for the first stage fuel to trigger the first timer.   This meant that the LR87 was shut down BEFORE stage separation and was fully out of thrust production AT stage separation.    As I stated above the First stage was always shut down before it ran out of fuel!   I fly in JNSQ and the Titan I can have issues orbiting payload in JNSQ.    I have NOT tested the Fuel drain set to 7% but I imagine some bumps, burbles and interesting things can happen.   This is pretty close to the real life Titan I launch... so, I guess, welcome to MY BDB realism setup :D

Pics or it didn't happen:

Spoiler

ZGdM6BF.jpg

Here is my over all Titan I with the AJ100/SOLTAN SRB.     Note I use 4x of the bottom UA-120x SRM seperation motors on each SRM 180 degrees out of phase from each other... one above and 1 below the decoupler.    For the Soltan I prefer the stock TT70 Radial Decoupler.   I have had too many SOLTANs break my rockets otherwise.

5fGHYDG.jpg

Smart part set to 3% fuel to stage the next stage (activate LR87-AJ-3)    On left Hand booster from "start" in VAB.

AjIAtmF.jpg

Right Hand SRB with Drain Smart Part set to 0%.   Again it just stages the next stage.   Which separates the SRBs from the Titan I stack

b37lJOi.jpg

As I tested it the Fuel Drain on the 1st Stage is set to 6%  It activates Action Group 10

bTiRnoM.jpg

HOW I SUGGEST you fly Titan I.   1st Stage Fuel drain is set to 7%! not 6% as above

o9QXWyk.jpg

This is Action group 10.   I have highlighted in the 3rd column the "Shutdown Engine" function that goes hand in hand with the "Activate Engine" function in the center column.    As I said in the text above.  you activate the BOTTOM "Activate Engine" option in your first action group.    Notice there is still another "Activate Engine" and "Shutdown Engine" pair further up in the right hand column.       Please also note the settings for the LR91-AJ-3 are stock DEFAULT BDB.  I did no altering/or editing to this part.... (except I think I added a Hypergolic version for some crazy reason!) 

Please also note in the left column, Action Group 08 is also lit up yellow.  This is because the LR91 gets it's second "Activate engine" in that  action group (the Top one!)

RMgAbz4.jpg

7 second timer that activates Action group 9  (note I used the HOSS GCU for this build. )

4HI1KQb.jpg

This is how I setup Action Group 9.   Notice MECO for Stage 1 is listed here

DOX5fRU.jpg

4 second timer on the opposite side of the HOSS (notice the door is now on the left hand side vs the other timer setup picture?)

dUBghHB.jpg

Action Group 8.   Just activate the UPPER LR91-AJ-3 "Activate Engine"

 

Spoiler

Here are a few pictures from my first attempt (5% fuel in Stage I tank) at getting this staging thing to work as per the Titan I book as pointed out by blowfish yesterday!

jYyegy0.jpg

5% fuel start 7 second timer and activate the LR91 Verniers only!)

VHAuWfk.jpg

RAN OUT OF FUEL IN THE FIRST STAGE TOO EARLY!

hj6gCVN.jpg

Separation with only the Verniers running on the LR91 (no flame from the main bell!)    

Sadly this was the last picture I took of this (or any of my other 2 test flights)   for Stage separation.

 

Edited by Pappystein
Pics or it didn't happen! +Formatting errors and changed one word from Hydrolox to Hypergolic
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Uh hey everyone I'm alive :) And I'm going to try and dev stream both days this weekend. Hopefully I'll be able to start getting a little momentum back. I also might try and play Age of Empires II with @Beale on stream one of the two days so swing by for that.

Focus this weekend will probably be blocking out the model for the new Apollo CSM.

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Just now, CobaltWolf said:

Uh hey everyone I'm alive :) And I'm going to try and dev stream both days this weekend. Hopefully I'll be able to start getting a little momentum back. I also might try and play Age of Empires II with @Beale on stream one of the two days so swing by for that.

Focus this weekend will probably be blocking out the model for the new Apollo CSM.

The most epic cross over event!

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On 1/21/2021 at 10:47 AM, CobaltWolf said:

Uh hey everyone I'm alive :) And I'm going to try and dev stream both days this weekend. Hopefully I'll be able to start getting a little momentum back. I also might try and play Age of Empires II with @Beale on stream one of the two days so swing by for that.

Focus this weekend will probably be blocking out the model for the new Apollo CSM.

Since no one did it or said it....

 

He's alive?   HE IS ALIVE!!!!   RUN! :D           Sorry I had to just re-watched the first 20 minutes of the best Frankenstein movie... on accident...  (and it is still playing in the background.)    Seriously I thought I was putting in Blazing Saddles!    Young Frankenstein.   

Now where is my Blazing Saddles Blu-Ray...    *Self edited and deleted Opinionated Jerk comments about picture quality streaming vs Blu-Ray*

 

Seriously, I hope I can at least catch the stream on Saturday.    Sunday is a work day for me so :/    But hey At-least I get three contiguous days off in a row right?

Titan II post latter today for certain.    Titan I edits HOPEFULLY latter today.      And I am experimenting with playing around with an alternative place to post them so you can find them all easy-ish (and I don't mean my long departed Great Grandma Ish!)

And I want to apologize for my *Opinionated Jerk* comments above about Blu-ray vs Streaming.   As a Picture Quality Professional I take pride in my work and to watch so many people stream low quality crap and say it is "the best picture quality" just because company X or Y paid a lot of money to put the latest means nearly nothing buzzwords on the work or say their streaming services fully meets the standards of said buzzwords....   grinds my gears :D 

 

 

Edited by Pappystein
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On 1/19/2021 at 3:48 PM, derega16 said:

When Past and Future collided

On those images, how did you get the white Fairings for the 5.6ish Diameter Parts?

all Mine Come out a Weird Gray

Ive Probably done something wrong as I ‘Pruned’ The BDB parts so I Only have about half ish the Parts.

however, someone help me please

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25 minutes ago, Ollz said:

On those images, how did you get the white Fairings for the 5.6ish Diameter Parts?

all Mine Come out a Weird Gray

Ive Probably done something wrong as I ‘Pruned’ The BDB parts so I Only have about half ish the Parts.

however, someone help me please

do you have a new version or an old version/ are you using deprecated parts?

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You asked for it.   You even provided new, forgotten sources to me....    For which I am eternally grateful.   I want these works to be as accurate as possible!    So First I give you the updated Titan I article:

 

 

The Still Mighty Titan II, Titan GLV and Titan 23G and other Titan II variants.

I am writing this on the assumption you have already read the Titan I article.   This article could be slightly confusing if you have not read that article first.

Early in the development of both the Atlas and Titan Missiles, the Remo-Wooldridge corporation, the soon to be TRW, pointed out to the USAF that a better fuel source than cryogenic Liquid Oxygen should be found.  Liquid Oxygen boils off at a prodigious rate when exposed to normal terrestrial temperatures.   The USAF approached both General Dynamics (Convair Division) and the Martin Company about converting to some form of storable liquid fuel.   Convair pointed out that a storable fuel would destroy the balloon tanks in short order… and the extra weight would inviolate their entire launch principal.   This quickly excluded Atlas from being “up fueled” to a new storable propellant.   You see, even today with all our advances in chemistry and metallurgy, storable fuels tend to be very caustic, very cancerous, and generally unbelievably BAD to be around.   Back in the 1950s we are talking about nitric acid and any of various fuel types that nitric acid self-combusts or goes hypergolic with.   Why is self-combustion an important factor for room temperature stored fuels?  The short answer is I do not know.   The longer answer involves a lot of chemical and engineering equations that deal with ISP.    I will stick with I DON’T KNOW because it is easier to say and takes up less space in this article… by tens of paragraphs! :D

 

Spoiler

Some of the fuels investigated, were declared too violent even in storage.   Things like High Test Peroxide.   Hydrogen Peroxide, readily available over the counter in 2% to 6% concentrations in normal water is a great astringent and wound sterilizer.  But at 80% to 90% concentration…. Can dissolve organic matter in moments… this includes an all-up Human, much to the chagrin of many German pilots in World War II who flew the ME-163 Komet in various forms as the HTP as the high percentage Hydrogen Peroxide is often called, would leak.   There being cases where Me-163s just exploded on the tarmac.    So in short, Hypergolic fuels require a lot of care when dealing with them.   More so that the Cryogenic LOX.  

The good news for Titan, was that this was 20 years latter and while Hypergolic rockets were tested and knowledge was gained, few were flown.    When it was decided to convert the Titan to Hypergolic fuel, it was a simple choice as Aerojet General was about the only rocket company in the US with then current Hypergolic fuel use between their AJ-10 engine as well as some of their semi disposable JATO/RATO aircraft takeoff assistance motors.   Aerojet had started to perfect their Hypergolic line even before being asked to convert the AJ-23 family of engines to Hypergolic fuels.   Even before being approached about converting the AJ-23 family to hypergolic fuels, Aerojet had begun developing their own custom fuel that would be easier to store and use than the previous they used.   Previously Aerojet was using Unsymmetrical dimethylhydrazine (UDMH) and inhibited red fuming nitric acid (IRFNA.)    The new fuel combination would also be unique in utilizing almost the same burn ratio as the KeroLOX fuel currently used in the Titan I rocket, by mass flow.   This new fuel was known as Aerozine50 and was a 50:50 mixture of UDMH and Hydrazine which are closely related to each other, and the improved Di-Nitrogen Tetroxide (NTO) was a replacement for IRFNA.  Aerojet catching on that the more corrosion inhibiter they added to their IRFNA mixture the better their engines burned.   Nitrogen Tetroxide or NTO was being used in the IRFNA formulation as a corrosion inhibiter in the fuel tank.   The More NTO added to the fuel mixture, the higher the ISP of the rocket stage….   So Aerojet just pulled the IRFNA and left NTO in the tanks and achieved the best performance yet.   To the improved NTO oxidizer, Aerojet would use a 50:50 mixture of UDMH and Hydrazine for fuel.  With the trade name Aerozine-50 (Az-50) this new mixture would burn more efficiently with NTO than any other fuel then tested.    While still caustic, corrosive, and cancerous, the combination of Az50 and NTO would greatly improve the safety of every rocket stage it was used on when compared to the previous UDMH/IRFNA fuel combination.  

This major leap did not come without problems, however.  Developing the new LR87 and LR91 AJ-5 variants took much more money and much longer than anticipated.   Enough so that the USAF instituted a CRASH program, one of the first times said type of program was initiated after WWII.   Aerojet, for about 6 months was confined to working on the problems with the LR87 and LR91 conversion to Hypergolic fuel.   While 6 months might seem like a short time, you must understand, everything else that Aerojet was doing was curtailed or in danger of being stopped by the USAF.  So, when in the same timeframe Aerojet submitted a version of the LR87 to power the upper stages of the ABMA Saturn I and V Rockets….  Well, that did not happen.  Even though Aerojet’s engine was best in 10 out of 11 criteria, Rocketdyne got the contract, and the J-2 exists.   You can read more about that in my pieces on the J-2 and E-1 engines.

How did the Titan II change from the Titan I?   Well knowing all the problems that Titan I had with stage separation, including several photographs from space showing the interstage collapsed in or exploded out preventing separation…   Martin changed how the two stages would separate.   Like on the previous Titan I, the Titan II would utilize a zero-ullage motor 2nd stage start aka the “fire in the hole” method.   This meaning the 2nd stage was started while the first stage was still or just powering down.  The big difference is the first stage would add thrust cancelation motors which were not powerful enough to completely stop the 1st stage at full thrust, were more than powerful enough to overcome the turbopumps exhaust thrust.   It was believed that the Titan I turbopumps ran for several moments after the stop thrust commands were sent.   This proved to be mostly true.   It turns out that there is still quit a bit of fuel flowing to the engine after the stop thrust command is issued.   This is caused by the flow rate and the distance traveled after the fuel shutoff valves.   It is these same reasons why the LR87 takes so long to get to full thrust in the game.   If you are not using any of the upper stage patches or Spool patches in BDB you can clearly see this after you shut off the First stage Titan engine… it still provides meaningful thrust for several seconds.   But back to the changes.   Instead of a solid Interstage with blow-out panels.  The new Titan II with it’s larger diameter upper stage (the same 3.05m 10 ft as the lower stage now,) was believed to “block” most of the drag from leaving the interstage open.  Of course, this was not true but the loss in drag was more than made up for the much more powerful first stage as well as the much more reliable 2nd stage.   A major change to the design choice of the 2nd stage involved not using a two stage starting method for the LR91 as the Titan I had.   The Titan I as previously discussed activated the 4x vernier motors for almost 12 seconds of flight time before the main combustion chamber came on.   With the LR91-AJ-5 for Titan II, the entire role of the verniers was deleted.   This meant that the turbopump exhaust did not need to be augmented nor was it used in the same way.  Instead on the Titan II the turbopump exhaust would only provide roll control by a gimbal and twisting joint prior to the last 90-degree elbow pipe.    This greatly simplified both the startup of the 2nd stage as well as reduced the chances of damage to the 1st stage and the interstage structure like happened to the Titan I with some regularity early in it’s flight testing.    This also allowed the engineers at Martin to move the turbopump exhaust under the 2nd stage reducing parasitic drag and eliminating four high pressure points on the outside of the rocket as it accelerated to space.   Some documents claim that removing the 4 vernier exhaust from the airflow around the rocket more than offset the drag caused by open blow out panels on the interstage. 

A new warhead was eventually developed for the Titan II, it would be one of the largest service warheads ever produced and would stay on alert with the Titan II until their withdrawal starting in 1982.  A withdrawal due mostly to needing major manufacture level overhaul that would be needed to serve further, not due to any sort of treaty as many “historical documents” will contend.   Titan II was not deactivated due to any arms reduction talks.   However it’s removal from service would affect current and future talks in the mid 1980s and early 1990s arms control talks.

After it was retired from service many in the USAF had the bright idea to combine useable stages from the remaining missiles to create a cheap space launcher since every other launcher was soon to leave service…. As the result of the Space Shuttle.    Of course, history would stop the process of canceling the disposable rockets with the Challenger disaster in January 1986.   Challenger happened right in the middle of the USAF looking into such a conversion of the remaining Titan II stages.  Of 56 surviving Titan II missiles, only the 14 best were initially chosen for conversion.   Be it due to miss-handling or just over all dilapidated status, as a sign of the quality of the 2nd stage, a 15th second stage was sent to Martin Marietta as part of the conversion process.     After the initial orders were placed, it was quickly discovered that to fully update the Titan II ICBM into a space launcher would become prohibitive quickly due to the dilapidated state of the rockets and the cost of further conversions was, to put it mildly, more expensive than the just entering service new production satellite launchers of similar performance.   When all was said and done, only a few Titan II stages were still sound enough to be converted to Satellite launch vehicles.   These refurbished Titan II missiles received a new deployment bus atop the 2nd stage and a standardized fairing based on those used on other rockets.   There is a very nice picture of this on the 14th and final Titan II(23)G at the Evergreen air museum.  https://upload.wikimedia.org/wikipedia/commons/7/7c/LGM-25C_Titan_II_%286586628193%29_%282%29.jpg

   Some of the Titan II 2nd stages received an “ACS” system which is a self-contained Reaction control system, to orient the 2nd stage after burnout to properly deploy the 3rd stage or payload.   While ACS is not completely installed in the photo above, you can see the off-colored patches as well as the tubes the control wires run down from the avionics structure below the fairing.   In the end, the Titan IIG(23G) was available to launch a few payloads when launchers were hard to come by.   But it was not cheap and when launchers became available again in the form of the Delta II, the Titan IIG faded into history.   It should be noted that the Titan 23G is not correct following USAF naming standards.   The 23 series of Titan Rockets were equipped with LR87 and LR91 engines of the AJ-11 subset.  The Titan IIG flew with it’s original, but recertified, LR87-AJ-5 and LR91-AJ-5 engines.   Given at the time, the USAF designation standards were being converted from a “HARD” standard to a “HANDBOOK” this is not totally surprising.   This is why most documents in open publication have 4 different names assigned to the Titan II derived SLV.  They are: Titan IISLV, Titan II(23G), Titan IIG(23G), and Titan 23G.     More permutations if you sub the

 

The Semi-related Titan II.5 and Titan IIGLV were proposals and actual flight articles for the Gemini program.   Initially Martin corporation proposed the Titan II.5 to NASA, it would have a slight stretch to take advantage of the lighter Gemini capsule payload and provide better orbital dynamics for the Gemini program.   I have found no actual documents detailing the proposal in detail, but Ed Kyle of Space Launch report suggested a 40” stretch to the first stage.   Every document I have found on the Titan II.5 suggests that NASA was seriously considering it.   Given the issues with Pogo we will discuss in the next few paragraphs it was a good decision by NASA to NOT accept a new version of Titan and rather just alter the Titan II into the Titan II GLV.    Titan II.5 is not buildable as described but a reasonable facsimile can be made by using the Titan IIIM first stage tank setup and reducing the fuel slightly.

The Titan II GLV was a program that was relatively on time.  RARE for a government acquisition.   Starting with the base Titan II that was just entering testing for the USAF, NASA developed the appropriate changes to the basic Rocket that would be required for NASA to feel safe putting astronauts on board.  Chiefly the changes centered around lowering the pressure in the turbines of the engines, and many thousands of built-in test sensors throughout the spaceframe.   Here is where things get hinky... this is also why Aerojet General was forced into the CRASH program for their new LR87 and LR91 AJ-5s….   POGO.  Pogo is a vertical (through the body of the rocket) oscillation resulting in up-to several gees of positive and negative acceleration along the flight direction with a rapid repetition.  This can lead to structural failure, and in the case of pilots, injury, or death.   In USAF tests Pogo was only experienced once… as seen by their test instruments.  Since the USAF does not use as many test instruments for launches as NASA did, it is not surprising that many launches that entered Pogo went un-detected.  So, NASA sort of pressured the USAF to add extra test equipment to the next few test Launches of the Titan II.   What was found resulted in a lot of re-engineering of the new hypergolic LR87 and LR91 engines as well as the fuel pipes and tanks on the rocket stages themselves.  These changes reduced the vertical oscillations to significantly less than 1g of acceleration and much less often than the 11hz or 11x per second the pogo was detected initially.   Most of the “anti-Pogo” changes involved flex lines in the fuel system (instead of rigid fuel lines) as well as flow rate dampers in the fuel system itself to prevent over acceleration of the fuel or oxidizer in the engines (leading to altered burn profiles.)    These changes are the prime result in the Titan II having few “failed launches” when compared to the Titan I.   The base Titan II would have 77 successful flights on 81 launches.   A much higher ratio of success when compared to the previous Titan I variant.  When you add the Titan GLV and the converted Titan 23Gs mentioned above the launch ratio is 101 to 107 with only one Titan 23G failure out of the additional 24 launches.   It should be noted that several early launches in the USAF test program, where POGO was present, were still considered a success and are not counted as failures as the warhead simulator landed near enough the target zone to be considered successful.  

In BDB we can build the All-up Titan II missile… the warhead is replaced by an aerodynamic cover.   We can also make the All-Up Titan IIGLV.  However, we are unable to make the Titan II.5 mostly because there is no real-world data.  You can make a loose analog by using the Titan IIIM first stage tanks with a small reduction in max fuel.   In the case of this conversion to a Titan II.5 every other part beyond the upper first stage tank is the same as the Titan IIGLV.  

Lastly, we can build ANY version of the Titan 23G satellite launcher including the Titan 2S, Titan 2L and 3L.  The Titan 2S would be a core Titan 23G with the addition of either Castor IV SRMs or GEM-40 SRMs.   The SRMs would be mounted in quantities starting at 4 and ending at 10.  If 10 rockets were carried, they would be burned in a 4, 4, 2 or 4,3,3 profile.  Such a combination would double the payload of the Titan 23G but would cause problems because a new aft skirt (the engine mount in BDB parlance) to protect the AJ-5 engine (just switch to the “Titan III” engine mount type when you have your AJ5 engine installed) and would require structural changes to the core.  Given that only ~23 all up Titan 23Gs were possible to make this would have been an expensive undertaking.  The Titan 23G(S) or Titan 2S is fully buildable in BDB.  The Titan 2L would be a Titan 23G with 2 Titan 23G first stages strapped on as boosters.  All 3 engines would ignite and burn at the same fuel rate (booster and 1st stage.) and all three would burn out and separate at the same time.   The Titan 3L would use the Commercial Titan 3 core but with Titan II AJ-5 engines on the first stage.  As it is using the Commercial Titan 3 as the core stage it would use Titan IIIM tanks.   Just like the 2L the 3L would ignite all 3 LR87-AJ-5s at once.    It is unclear if the Commercial Titan 3 2nd stage would use the LR91-AJ-11A of the nominal production or use the LR91-AJ-5 for the 2nd stage.  Given how few of the LR91s survived to be considered re-usable it is likely the Titan 3L would use Titan IV 2nd stage tanks made new, and the LR91-AJ-11A of the CT3 and Titan IV.

While there were enough first stages and spare engines that were of enough quality to consider the concept, it is unlikely that the 3L would have flown as designed and instead I feel the best “Liquid boosted Titan” to build is the Titan 2L.   The Titan 2L is fully buildable in BDB and 3L is nearly completely buildable.   Only the CT3’s AJ-11A engine upgrade is missing to fully give this rocket it’s due.   The Titan 3L would fly with the CT3’s fairing as well I should mention.

There are a lot of variants of the Titan II that can be fully built in BDB.    In-fact there is one I have not mentioned.   The Titan IIIA.

Err WHAT!  The Titan IIIA is a Titan III you say?  WRONG.  The Titan IIIA was a proof-of-concept rocket and is closer to the Titan II than any other Titan III.   First off, the Titan IIIA flew with LR87-AJ-5 and LR91-AJ-5 engines.  With one exception, it is the only Titan III to do so.    Secondly, while the Titan IIIA did have the slight second stage Stretch associated with all Titan IIIs that was the only change vs the Titan II that was integrated into the Titan IIIA.       

So Titan IIIA has the longer 2nd stage tank… But is otherwise a Titan II that carries Transtage.   We will see this generational kind of mix of technology in the real Titan III family which is the subject of one of our next articles.

 

Edited by Pappystein
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1 hour ago, Pappystein said:

You asked for it.   You even provided new, forgotten sources to me....    For which I am eternally grateful.   I want these works to be as accurate as possible!    So First I give you the updated Titan I article:

 

 

The Still Mighty Titan II, Titan GLV and Titan 23G and other Titan II variants.

I am writing this on the assumption you have already read the Titan I article.   This article could be slightly confusing if you have not read that article first.

Early in the development of both the Atlas and Titan Missiles, the Remo-Wooldridge corporation, the soon to be TRW, pointed out to the USAF that a better fuel source than cryogenic Liquid Oxygen should be found.  Liquid Oxygen boils off at a prodigious rate when exposed to normal terrestrial temperatures.   The USAF approached both General Dynamics (Convair Division) and the Martin Company about converting to some form of storable liquid fuel.   Convair pointed out that a storable fuel would destroy the balloon tanks in short order… and the extra weight would inviolate their entire launch principal.   This quickly excluded Atlas from being “up fueled” to a new storable propellant.   You see, even today with all our advances in chemistry and metallurgy, storable fuels tend to be very caustic, very cancerous, and generally unbelievably BAD to be around.   Back in the 1950s we are talking about nitric acid and any of various fuel types that nitric acid self-combusts or goes hypergolic with.   Why is self-combustion an important factor for room temperature stored fuels?  The short answer is I do not know.   The longer answer involves a lot of chemical and engineering equations that deal with ISP.    I will stick with I DON’T KNOW because it is easier to say and takes up less space in this article… by tens of paragraphs! :D

Some of the fuels investigated, were declared too violent even in storage.   Things like High Test Peroxide.   Hydrogen Peroxide, readily available over the counter in 2% to 6% concentrations in normal water is a great astringent and wound sterilizer.  But at 80% to 90% concentration…. Can dissolve organic matter in moments… this includes an all-up Human, much to the chagrin of many German pilots in World War II who flew the ME-163 Komet in various forms as the HTP as the high percentage Hydrogen Peroxide is often called, would leak.   There being cases where Me-163s just exploded on the tarmac.    So in short, Hypergolic fuels require a lot of care when dealing with them.   More so that the Cryogenic LOX.  

The good news for Titan, was that this was 20 years latter and while Hypergolic rockets were tested and knowledge was gained, few were flown.    When it was decided to convert the Titan to Hypergolic fuel, it was a simple choice as Aerojet General was about the only rocket company in the US with then current Hypergolic fuel use between their AJ-10 engine as well as some of their semi disposable JATO/RATO aircraft takeoff assistance motors.   Aerojet had started to perfect their Hypergolic line even before being asked to convert the AJ-23 family of engines to Hypergolic fuels.   Even before being approached about converting the AJ-23 family to hypergolic fuels, Aerojet had begun developing their own custom fuel that would be easier to store and use than the previous they used.   Previously Aerojet was using Unsymmetrical dimethylhydrazine (UDMH) and inhibited red fuming nitric acid (IRFNA.)    The new fuel combination would also be unique in utilizing almost the same burn ratio as the KeroLOX fuel currently used in the Titan I rocket, by mass flow.   This new fuel was known as Aerozine50 and was a 50:50 mixture of UDMH and Hydrazine which are closely related to each other, and the improved Di-Nitrogen Tetroxide (NTO) was a replacement for IRFNA.  Aerojet catching on that the more corrosion inhibiter they added to their IRFNA mixture the better their engines burned.   Nitrogen Tetroxide or NTO was being used in the IRFNA formulation as a corrosion inhibiter in the fuel tank.   The More NTO added to the fuel mixture, the higher the ISP of the rocket stage….   So Aerojet just pulled the IRFNA and left NTO in the tanks and achieved the best performance yet.   To the improved NTO oxidizer, Aerojet would use a 50:50 mixture of UDMH and Hydrazine for fuel.  With the trade name Aerozine-50 (Az-50) this new mixture would burn more efficiently with NTO than any other fuel then tested.    While still caustic, corrosive, and cancerous, the combination of Az50 and NTO would greatly improve the safety of every rocket stage it was used on when compared to the previous UDMH/IRFNA fuel combination.  

This major leap did not come without problems, however.  Developing the new LR87 and LR91 AJ-5 variants took much more money and much longer than anticipated.   Enough so that the USAF instituted a CRASH program, one of the first times said type of program was initiated after WWII.   Aerojet, for about 6 months was confined to working on the problems with the LR87 and LR91 conversion to Hypergolic fuel.   While 6 months might seem like a short time, you must understand, everything else that Aerojet was doing was curtailed or in danger of being stopped by the USAF.  So, when in the same timeframe Aerojet submitted a version of the LR87 to power the upper stages of the ABMA Saturn I and V Rockets….  Well, that did not happen.  Even though Aerojet’s engine was best in 10 out of 11 criteria, Rocketdyne got the contract, and the J-2 exists.   You can read more about that in my pieces on the J-2 and E-1 engines.

How did the Titan II change from the Titan I?   Well knowing all the problems that Titan I had with stage separation, including several photographs from space showing the interstage collapsed in or exploded out preventing separation…   Martin changed how the two stages would separate.   Like on the previous Titan I, the Titan II would utilize a zero-ullage motor 2nd stage start aka the “fire in the hole” method.   This meaning the 2nd stage was started while the first stage was still or just powering down.  The big difference is the first stage would add thrust cancelation motors which were not powerful enough to completely stop the 1st stage at full thrust, were more than powerful enough to overcome the turbopumps exhaust thrust.   It was believed that the Titan I turbopumps ran for several moments after the stop thrust commands were sent.   This proved to be mostly true.   It turns out that there is still quit a bit of fuel flowing to the engine after the stop thrust command is issued.   This is caused by the flow rate and the distance traveled after the fuel shutoff valves.   It is these same reasons why the LR87 takes so long to get to full thrust in the game.   If you are not using any of the upper stage patches or Spool patches in BDB you can clearly see this after you shut off the First stage Titan engine… it still provides meaningful thrust for several seconds.   But back to the changes.   Instead of a solid Interstage with blow-out panels.  The new Titan II with it’s larger diameter upper stage (the same 3.05m 10 ft as the lower stage now,) was believed to “block” most of the drag from leaving the interstage open.  Of course, this was not true but the loss in drag was more than made up for the much more powerful first stage as well as the much more reliable 2nd stage.   A major change to the design choice of the 2nd stage involved not using a two stage starting method for the LR91 as the Titan I had.   The Titan I as previously discussed activated the 4x vernier motors for almost 12 seconds of flight time before the main combustion chamber came on.   With the LR91-AJ-5 for Titan II, the entire role of the verniers was deleted.   This meant that the turbopump exhaust did not need to be augmented nor was it used in the same way.  Instead on the Titan II the turbopump exhaust would only provide roll control by a gimbal and twisting joint prior to the last 90-degree elbow pipe.    This greatly simplified both the startup of the 2nd stage as well as reduced the chances of damage to the 1st stage and the interstage structure like happened to the Titan I with some regularity early in it’s flight testing.    This also allowed the engineers at Martin to move the turbopump exhaust under the 2nd stage reducing parasitic drag and eliminating four high pressure points on the outside of the rocket as it accelerated to space.   Some documents claim that removing the 4 vernier exhaust from the airflow around the rocket more than offset the drag caused by open blow out panels on the interstage. 

A new warhead was eventually developed for the Titan II, it would be one of the largest service warheads ever produced and would stay on alert with the Titan II until their withdrawal starting in 1982.  A withdrawal due mostly to needing major manufacture level overhaul that would be needed to serve further, not due to any sort of treaty as many “historical documents” will contend.   Titan II was not deactivated due to any arms reduction talks.   However it’s removal from service would affect current and future talks in the mid 1980s and early 1990s arms control talks.

After it was retired from service many in the USAF had the bright idea to combine useable stages from the remaining missiles to create a cheap space launcher since every other launcher was soon to leave service…. As the result of the Space Shuttle.    Of course, history would stop the process of canceling the disposable rockets with the Challenger disaster in January 1986.   Challenger happened right in the middle of the USAF looking into such a conversion of the remaining Titan II stages.  Of 56 surviving Titan II missiles, only the 14 best were initially chosen for conversion.   Be it due to miss-handling or just over all dilapidated status, as a sign of the quality of the 2nd stage, a 15th second stage was sent to Martin Marietta as part of the conversion process.     After the initial orders were placed, it was quickly discovered that to fully update the Titan II ICBM into a space launcher would become prohibitive quickly due to the dilapidated state of the rockets and the cost of further conversions was, to put it mildly, more expensive than the just entering service new production satellite launchers of similar performance.   When all was said and done, only a few Titan II stages were still sound enough to be converted to Satellite launch vehicles.   These refurbished Titan II missiles received a new deployment bus atop the 2nd stage and a standardized fairing based on those used on other rockets.   There is a very nice picture of this on the 14th and final Titan II(23)G at the Evergreen air museum.  https://upload.wikimedia.org/wikipedia/commons/7/7c/LGM-25C_Titan_II_%286586628193%29_%282%29.jpg

   Some of the Titan II 2nd stages received an “ACS” system which is a self-contained Reaction control system, to orient the 2nd stage after burnout to properly deploy the 3rd stage or payload.   While ACS is not completely installed in the photo above, you can see the off-colored patches as well as the tubes the control wires run down from the avionics structure below the fairing.   In the end, the Titan IIG(23G) was available to launch a few payloads when launchers were hard to come by.   But it was not cheap and when launchers became available again in the form of the Delta II, the Titan IIG faded into history.   It should be noted that the Titan 23G is not correct following USAF naming standards.   The 23 series of Titan Rockets were equipped with LR87 and LR91 engines of the AJ-11 subset.  The Titan IIG flew with it’s original, but recertified, LR87-AJ-5 and LR91-AJ-5 engines.   Given at the time, the USAF designation standards were being converted from a “HARD” standard to a “HANDBOOK” this is not totally surprising.   This is why most documents in open publication have 4 different names assigned to the Titan II derived SLV.  They are: Titan IISLV, Titan II(23G), Titan IIG(23G), and Titan 23G.     More permutations if you sub the

 

The Semi-related Titan II.5 and Titan IIGLV were proposals and actual flight articles for the Gemini program.   Initially Martin corporation proposed the Titan II.5 to NASA, it would have a slight stretch to take advantage of the lighter Gemini capsule payload and provide better orbital dynamics for the Gemini program.   I have found no actual documents detailing the proposal in detail, but Ed Kyle of Space Launch report suggested a 40” stretch to the first stage.   Every document I have found on the Titan II.5 suggests that NASA was seriously considering it.   Given the issues with Pogo we will discuss in the next few paragraphs it was a good decision by NASA to NOT accept a new version of Titan and rather just alter the Titan II into the Titan II GLV.    Titan II.5 is not buildable as described but a reasonable facsimile can be made by using the Titan IIIM first stage tank setup and reducing the fuel slightly.

The Titan II GLV was a program that was relatively on time.  RARE for a government acquisition.   Starting with the base Titan II that was just entering testing for the USAF, NASA developed the appropriate changes to the basic Rocket that would be required for NASA to feel safe putting astronauts on board.  Chiefly the changes centered around lowering the pressure in the turbines of the engines, and many thousands of built-in test sensors throughout the spaceframe.   Here is where things get hinky... this is also why Aerojet General was forced into the CRASH program for their new LR87 and LR91 AJ-5s….   POGO.  Pogo is a vertical (through the body of the rocket) oscillation resulting in up-to several gees of positive and negative acceleration along the flight direction with a rapid repetition.  This can lead to structural failure, and in the case of pilots, injury, or death.   In USAF tests Pogo was only experienced once… as seen by their test instruments.  Since the USAF does not use as many test instruments for launches as NASA did, it is not surprising that many launches that entered Pogo went un-detected.  So, NASA sort of pressured the USAF to add extra test equipment to the next few test Launches of the Titan II.   What was found resulted in a lot of re-engineering of the new hypergolic LR87 and LR91 engines as well as the fuel pipes and tanks on the rocket stages themselves.  These changes reduced the vertical oscillations to significantly less than 1g of acceleration and much less often than the 11hz or 11x per second the pogo was detected initially.   Most of the “anti-Pogo” changes involved flex lines in the fuel system (instead of rigid fuel lines) as well as flow rate dampers in the fuel system itself to prevent over acceleration of the fuel or oxidizer in the engines (leading to altered burn profiles.)    These changes are the prime result in the Titan II having few “failed launches” when compared to the Titan I.   The base Titan II would have 77 successful flights on 81 launches.   A much higher ratio of success when compared to the previous Titan I variant.  When you add the Titan GLV and the converted Titan 23Gs mentioned above the launch ratio is 101 to 107 with only one Titan 23G failure out of the additional 24 launches.   It should be noted that several early launches in the USAF test program, where POGO was present, were still considered a success and are not counted as failures as the warhead simulator landed near enough the target zone to be considered successful.  

In BDB we can build the All-up Titan II missile… the warhead is replaced by an aerodynamic cover.   We can also make the All-Up Titan IIGLV.  However, we are unable to make the Titan II.5 mostly because there is no real-world data.  You can make a loose analog by using the Titan IIIM first stage tanks with a small reduction in max fuel.   In the case of this conversion to a Titan II.5 every other part beyond the upper first stage tank is the same as the Titan IIGLV.  

Lastly, we can build ANY version of the Titan 23G satellite launcher including the Titan 2S, Titan 2L and 3L.  The Titan 2S would be a core Titan 23G with the addition of either Castor IV SRMs or GEM-40 SRMs.   The SRMs would be mounted in quantities starting at 4 and ending at 10.  If 10 rockets were carried, they would be burned in a 4, 4, 2 or 4,3,3 profile.  Such a combination would double the payload of the Titan 23G but would cause problems because a new aft skirt (the engine mount in BDB parlance) to protect the AJ-5 engine (just switch to the “Titan III” engine mount type when you have your AJ5 engine installed) and would require structural changes to the core.  Given that only ~23 all up Titan 23Gs were possible to make this would have been an expensive undertaking.  The Titan 23G(S) or Titan 2S is fully buildable in BDB.  The Titan 2L would be a Titan 23G with 2 Titan 23G first stages strapped on as boosters.  All 3 engines would ignite and burn at the same fuel rate (booster and 1st stage.) and all three would burn out and separate at the same time.   The Titan 3L would use the Commercial Titan 3 core but with Titan II AJ-5 engines on the first stage.  As it is using the Commercial Titan 3 as the core stage it would use Titan IIIM tanks.   Just like the 2L the 3L would ignite all 3 LR87-AJ-5s at once.    It is unclear if the Commercial Titan 3 2nd stage would use the LR91-AJ-11A of the nominal production or use the LR91-AJ-5 for the 2nd stage.  Given how few of the LR91s survived to be considered re-usable it is likely the Titan 3L would use Titan IV 2nd stage tanks made new, and the LR91-AJ-11A of the CT3 and Titan IV.

While there were enough first stages and spare engines that were of enough quality to consider the concept, it is unlikely that the 3L would have flown as designed and instead I feel the best “Liquid boosted Titan” to build is the Titan 2L.   The Titan 2L is fully buildable in BDB and 3L is nearly completely buildable.   Only the CT3’s AJ-11A engine upgrade is missing to fully give this rocket it’s due.   The Titan 3L would fly with the CT3’s fairing as well I should mention.

There are a lot of variants of the Titan II that can be fully built in BDB.    In-fact there is one I have not mentioned.   The Titan IIIA.

Err WHAT!  The Titan IIIA is a Titan III you say?  WRONG.  The Titan IIIA was a proof-of-concept rocket and is closer to the Titan II than any other Titan III.   First off, the Titan IIIA flew with LR87-AJ-5 and LR91-AJ-5 engines.  With one exception, it is the only Titan III to do so.    Secondly, while the Titan IIIA did have the slight second stage Stretch associated with all Titan IIIs that was the only change vs the Titan II that was integrated into the Titan IIIA.       

So Titan IIIA has the longer 2nd stage tank… But is otherwise a Titan II that carries Transtage.   We will see this generational kind of mix of technology in the real Titan III family which is the subject of one of our next articles.

Man, these are really long. They're great, but maybe you could put them in a spoiler? 

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2 hours ago, Pappystein said:

Early in the development of both the Atlas and Titan Missiles, the Remo-Wooldridge corporation, the soon to be TRW, pointed out to the USAF that a better fuel source than cryogenic Liquid Oxygen should be found.  Liquid Oxygen boils off at a prodigious rate when exposed to normal terrestrial temperatures.   The USAF approached both General Dynamics (Convair Division) and the Martin Company about converting to some form of storable liquid fuel.   Convair pointed out that a storable fuel would destroy the balloon tanks in short order… and the extra weight would inviolate their entire launch principal.   This quickly excluded Atlas from being “up fueled” to a new storable propellant.   You see, even today with all our advances in chemistry and metallurgy, storable fuels tend to be very caustic, very cancerous, and generally unbelievably BAD to be around.   Back in the 1950s we are talking about nitric acid and any of various fuel types that nitric acid self-combusts or goes hypergolic with.   Why is self-combustion an important factor for room temperature stored fuels?  The short answer is I do not know.   The longer answer involves a lot of chemical and engineering equations that deal with ISP.    I will stick with I DON’T KNOW because it is easier to say and takes up less space in this article… by tens of paragraphs!

Mobile users would appreciate if you putt walls-o-text in a spoiler :)

You would appreciate this book. Aside from it's tendency to go boom at inconvenient times, freezing point of storable fuels is a huge factor.

tQEYVvv.png

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2 hours ago, Jso said:

Mobile users would appreciate if you putt walls-o-text in a spoiler :)

You would appreciate this book. Aside from it's tendency to go boom at inconvenient times, freezing point of storable fuels is a huge factor.

tQEYVvv.png

Thanks Jso.   I have tried to read an E-book version of this but found it kind of hard to read that way.   The portions I could track on the E-reader were HILARIOUS and even if you are not a Aerospace nerd the book can be down right funny.   BUT I never finished it because I like to re-refrence older pages while reading.  Something just not easy to do in an E-Reader.    So, clicking on the link above,  I just HAD to order a physical copy today.    But, as far as the article is concerned I will stick with my "DON'T KNOW" as the simple answer to not create a text wall within a text wall.

Also altered the latest Titan II into a intro + Spoiler.

Please, @alberro+ and Jso, let me know if that works out better.    I will have to alter the next article slightly as there really isn't a good "intro" to it...  

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