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NoClass

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  1. Interesting...

    I've been running experiments too, because there's an irritating lack of documentation on how science is supposed to work...

    Still, I haven't noticed any difference in recovery yield through EVA activation. Specifically, I'm getting 5.4 science for recovering a Seismic Accelerometer mounted to a MK2 can on the launch pad. This is true if Bob (lvl 2 sci) is in the can or on EVA.

    So your results are curious to me. How exactly are you activating "manually" on EVA? I'm assuming that means that you are controlling the scientist on EVA, getting close to the experiment module, then right clicking to perform the experiment.

    The only difference the scientist seems to make for me is on the transmission efficiency, which turns to "basic analysis" (in yellow), regardless if the scientist activates manually or is in the can. (Though there is supposed to be a bonus, I get 2.4 regardless. That might be a rounding issue). This is in contrast to what the wiki currently says, that scientists give a bonus to "recovery". It's clearly a bonus to transmission, just like in the Beta.

    Interestingly enough, I've noticed that the "basic analysis" bonus stays even after the scientist has left the craft and walked away. Using brackets [ ] to switch between craft doesn't seem to reset this bonus, but switching to the space center does reset the bonus. I assume that switching to a distant craft on the map will reset it as well. Experiments collected by non-scientists on EVA don't show the "basic analysis" bonus, even if they're added to a craft with a scientist on board.

    It would be great if there was some sort of authority out there on how this is supposed to work.

  2. yeah it does, it was first noticed by airline pilots who noticed their craft being floaty and hard to slow when landings, i would use stock aero but i would prefer a sharper change, one not based on speed, i cannot unfortunatly code as yet but i was thinking maby a plugin that increased the lift/drag multiplyer in the debug and reduced the drag multiplyer, i didnt know of anywhere else to look for an aero dynamic plugin, i tried starting my own thread but nothing came of it... i was not thinking of necessarily adding it into FAR as that has a stearling reputation for excelent accuracy, but maby a seperate mod, to augment the stock aero to makee a noticable difference when close to the ground at any speed

    It would be nice to have, allowing slightly easier takeoffs for heavier planes, but I figure if ferram hasn't added it to FAR yet, then it's more complicated than it seems.

  3. the benifit in this gase is the possibilityof WIG craft, for which i have a certain passion, from what he said before accurate calculation is very difficult, but i am looking for approximate simulation, somthing that will make wig craft work, similarly to how the old aero model was made so that aircraft would work, somthing that will increase lift and decrease drag as you near the ground

    Doesn't ground effect have a huge impact for takeoffs and landings for all craft?

  4. How can I work out the speed for best rate of climb for a plane? Since spending ages getting to altitude sacks. Wikipedia mentions it's the speed with maximum excess power; FAR shows a "Specific Excess Power" data point so do I just want that high?

    My understanding is that it's also generally close to where you have maximum L/D, which is related to both a particular speed and AOA. (I use an AOA, because it shouldn't vary with altitude)

    ...but I don't know how much your actual thrust angle affects best rate of climb if you have high TWR.

    What I'd love to predict is best range speeds/altitudes for craft while constructing.

  5. Regarding wingtip winglets

    Anyway, yes, they will help. Perhaps not to the same extent as in real life (they might be more or less effective than they should be, depending on the design), but they do help. This assumes that a significant portion of your drag is due to lift though.

    Whoah?! Really? That's awesome! I guess I have no freaking clue how FAR actually figures out induced drag. Any chance you could explain that? (not actual induced drag, but FARs method)

  6. If you want a tip you can try to use some part that goes perfect on symetry like the cubic octogonal strut and use it as a reference when positioning the control surfaces.

    Hrmm, how would this help with vertical symmetry?

    Actually, here's a deeper question: Are we sure that the control surfaces are actually misaligned? There may be a difference between where a part is drawn on the screen, and where it is calculated to be for the sake of game physics.

    Also, if you play around with it, you'll notice that the round pieces of the control surfaces are perfectly aligned. I don't know if this is significant.

    Mysteries!

  7. I would place both manually on a plane, to make sure they are aligned, but at moment I don't have time.

    Here goes.

    I thought at first that it might be a clipping problem. You'll notice that wings in tetryds's post are overlapping slightly, despite the fact that they were placed on a centerline using symmetry. It's funny, because I noticed that in recent KSP versions, it can be hard to get a bilaterally placed part to appear. You kinda have to massage it into position for the part to pop up on the other side.

    Anyway, to eliminate clipping, I simply moved the wing down the side of the tank.

    LOoXZjS.pngDelta Wings Placed Bilaterally near the top of a tank, with Small CS, Hosted by imgur.com

    ...same problem.

    So I did as asked, individually placing wings on top, and wings slightly lower.

    aaMC8S4.pngSwept Wings Placed Individually on the Top of a tank, with Small CS, Hosted by imgur.com

    pYtuFIc.pngSwept Wings Placed Individually near the Top of a Tank, with Small CS,Hosted by imgur.com

    I also tried bilaterally placing the wings, but individually placing the Small CSs, but to no avail. I'll spare you the pics. You'll also notice that I used both delta wings and swept wings. They all seem to just be flipped, and are not symmetrical in the horizontal plane.

    *sigh* This is making me OCD.

  8. This trick isn't 100%, but it can help....

    Use landing legs (LT-1's) to brace your craft, they can push against parts of your rocket and against each other, and of course they fold away when not in use :)

    That's... interesting!

    The only input I have is something I read (can't remember where) about how SAS torque is applied in the KSP engine. That is, SAS torque is applied directly to the center of mass of the craft, rather than on the actual torque part. So, SAS parts on the wobbly section wont stabilize it unless the CoM is in the wobbly section.

    I'm curious about how SAS works WRT control surfaces, RCS, and gimbals on craft that can flex. Does SAS recognize when the control part has been moved relative to the CoM, and adjust input accordingly? Or do control parts move based on where they are in the craft file?

  9. Here's a technique I used, though it's from an old craft I no longer have (so no pics :( , words must suffice.)

    Basically, pick one of the craft and build a spacer part that fits snugly onto both docking ports in the assembly building. This part doesn't have to be fancy (and it will never fly), it's just a few structural components and docking ports that line up with the craft.

    If you save this part to a subassembly, you can then mount it to your other craft, and it will show you exactly where to put your ports on that other craft.

    FYI, it's really hard to get these things perfectly. Allow for a little bit of flex in your craft, and expect to be slightly off balance in flight.

  10. I don't know if it helps at all, but here's some screenshots of the CoL being weird...

    Y'all correct me if I'm wrong.

    In the VAB, the windline for CoL calculation purposes assumes that air flow is coming from the open door, rather than the roof (which is the way most rockets would be pointed). To get an accurate CoL using FAR, one must rotate a rocket to point out the door.

    Also the vector arrow on the "CoL" indicator doesn't appear to mean anything.

    (y'all can add me to the list of people who prefer the use of "Aerodynamic Center" to "Center of Lift")

  11. Thanks for the reply softweir, but it's just a simple engine-tank-decoupler giving me the problem. I've since tried resetting them. The depleted stage behaves as if it's CoM is down below the engines.

    I've been able to get the BACCs boosters to properly separate with a couple of seperatrons mounted to the top of each. That never used to be necessary, of course, but it functions as a workaround.

  12. It "feels" like aircraft take a very long time to slow down to glide speeds after the engine is cut, even with spoilers and speed brakes.
    I don't have any of my documentation in front of me so I am shooting from memory. But the F-16C can glide 15km for every 1000ft AGL.
    Dead stick engine out landing in an F-16. Take note of his air speed on the left side of the HUD.
    And after all, the pilot did dump all his fuel in which i did not.

    That's some good info!

    I had a long winded post explaining that the problem isn't so much with glide ratio, which seems right on, but that craft seem to hold onto their energy for waaay too long. In that video, our brave Viper driver flares about 10 seconds before touchdown, and kills about 75 kts of speed in that frame of time. (~ 215 to 150 kts, or ~105 to 75 m/s). I couldn't get even wide-winged planes to slow down that fast.

    ...then I dumped fuel (TAC fuel balancer). That's the missing piece.

    KSP parts tend to be a bit more dense than in the real world to begin with, so an aircraft full of gas will take a lot longer to slow down to max glide speed.

    TL,DR; Dumping a couple of tons of gas will radically change how quickly your craft slows.

  13. I mean not to claim I am right about how the drag in FAR behaves, I just feel that the planes I build do not behave like I would expect them to. I'm basing this "feel" of the little I have played flight sims and also the fact that airliners do not completely cut their throttle when landing.

    Thank you for all the hard work that has been put into this mod! It makes KSP so much better, and I wish only to help you improve it!

    Honestly, I've had the same "feel" as well when playing with FAR. Specifically, that something is off in the way drag is handled at relatively low speeds and high AoA. It "feels" like aircraft take a very long time to slow down to glide speeds after the engine is cut, even with spoilers and speed brakes.

    I won't tell you our feelings are wrong (Ferram will tell you that, though. He's a true engineer!), but I can posit some reasons why our feelings are wrong:

    -We're not used to aircraft designed for low drag and high TWRs. Many real world aircraft don't fly more than 1.5-3 times faster than their stall speeds, so an aircraft aerodynamically designed for high-speed/low-drag may indeed take a long time to get down to a slow flight regime. Does anyone know how long it takes an F-16 to get down to stall speed after cutting the engine in level flight?

    -The glide ratios and stall speeds of aircraft designed in FAR/KSP seem normal (at least to me, and I think you agree). This is hardly proof, but it would be very hard for FAR to be right about all the L/D derived slow flight numbers, but wrong about how low speed drag works in general.

    -I've noticed that bad installs of FAR after a KSP change can magnify this "feel." Everything will look to be normal, but some part of the drag model is missing because I am careless with my zips, and I do indeed have infinite gliders. Deleting and re-installing everything has solved 99% of the weirdness I've ever seen with this mod.

    ...or maybe the low speed drag model actually is a little off

  14. I replaced 6 with 2 to get a double cost of things; the only problem is that the recoveries will only be HALF of the total part now; which is okay by me but this might not work; I will give it a whirl on the next game restart.

    Cmdr Zeta

    Honestly, half price for an item recovered from space seems like a good deal. I may make this change myself.

    Well done answering your own question BTW. :)

  15. RoboRay has the best answer above, but I'd like to expand on one thing...

    ...the Centre of Lift goes behind the Centre of Mass, so our plane will tilt slightly downward when not controlled.

    Speaking precisely, a rear CoL will not by itself pitch the craft downward. All it will do is pull the tail out of the windline, away from the direction of flight.

    If there was no gravity then the aircraft would continue to point in the same direction. However, if you're not producing lift, gravity will begin to pull the direction of flight downward, the angle of the airflow will point downward, and your stable craft will follow.

    Aircraft that are nothing but tail (like an arrow or a fin-stabilized rocket) will follow a nice ballistic curve, with the nose pointed in the direction of flight (which curves) the whole time.

    But, if you have wings that produce lift, and hold the nose slightly above the direction of flight, you'll keep flying forward.

  16. Why doesnt CoL behind flip the plane from back to forward if it can flip plane backwards if CoL is in front of CoM?

    You must ask yourself, "Jetsim, where does the air flow?" In flight, the CoL will always pull the tail of the plane away from the flow of air, and move behind the CoM.

    If you were flying backwards, the air would be moving back to front, then the CoL would flip the plane backwards. Don't fly backwards!

  17. OTOH, when you're building spaceplanes, it's not unreasonable to assume that you're using top-line components. How does a Kerbal turbojet compare to something like an SR-71 engine?

    According to the J58 page on Wikipedia (blessed be the Font of All Knowledge) it's similar, but the KSP turbojet is still about 150% more powerful for its weight. The J58 is a 2700 kg engine thrusting 150kN wet and 110 dry. Of course KSP crams all the mass into a small exhaust section and calls that the "engine."

    I didn't read too much into the page, as it's late and I have a short attention span, but I didn't see anything about fuel flow, which I suspect is much higher at full 'burner than KSP. I also suspect the thrusts at various airspeeds are radically different (especially for low a/s).

    As an aside, props to Alshain for patient and respectful explanation of the basics.

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