[1.8-1.11] Advanced Jet Engine v2.17.0 (June 26)

[Cratzz]

33 minutes ago, blowfish said:

Okay hmm, nothing is obviously wrong, and I see effects on those engines (without RP).  Are you sure that even at 100% throttle, with the afterburner engaged (e.g. on the J75), you see no effects?  And not smoke either?  If so, could you try again without RealPlume and then post those two files again?

Because im still getting "can't find animation named "HeatAnimationEmissiveTurbofan" on said Jets, i didn't bother to do a test launch, but maybe i should have cause it works Thanks for the help!

[blowfish]

AJE v2.8.0 for KSP 1.2.2 is now available!

• Fix intakes that had IntakeAir removed, also remove it from some parts that no longer have intakes
• Throttle now responds much faster, closer to reality
• Afterburner throttle now responds much faster than core
• Display core and afterburner throttles separately for afterburning engines
• SABRE-like engines no longer distinguish between afterburner and core
• New ramjet module, should be much better than the old one
• RAPIER now has slightly improved efficiency

[s20dan]

I can't get the ramjet to generate any significant thrust in 1.2.2 with Realism Overhaul

[blowfish]

13 minutes ago, s20dan said:

I can't get the ramjet to generate any significant thrust in 1.2.2 with Realism Overhaul

Could you be a bit more specific?  What sort of thrust are you getting at what flight condition (altitude, mach)?  Note that ramjets will have pretty low TWR to begin with.

[s20dan]

19 minutes ago, blowfish said:

Could you be a bit more specific?  What sort of thrust are you getting at what flight condition (altitude, mach)?  Note that ramjets will have pretty low TWR to begin with.

Sorry I wasn't more specific.

 I have setup a better test craft and was able to generate more thrust this time, problem solved The issue I was having is that the description mentions that it works best over mach2 but my most recent test craft didn't really generate any meaningful thrust until over mach3.5. But I guess that is going to vary with altitude and intake area too. My previous craft were having trouble using the engine at mach 2.2 @ 10km.

 

Cheers anyway.

[JeeF]

Hey Blowfish!

I've done some diggin around and I couldn't find any specific info about what these entries mean:

https://github.com/KSP-RO/AJE/blob/master/GameData/AJE/Squad.cfg#L92 (till line 111)

Sadly, the CFG isn't commented, nor is the source file. Could you please share what do these mean and how they influence the engines?

Thank you!

[Drew Kerman]

On 4/16/2017 at 10:12 PM, blowfish said:

AJE v2.8.0 for KSP 1.2.2 is now available!

• Fix intakes that had IntakeAir removed, also remove it from some parts that no longer have intakes
• Throttle now responds much faster, closer to reality
• Afterburner throttle now responds much faster than core
• Display core and afterburner throttles separately for afterburning engines
• SABRE-like engines no longer distinguish between afterburner and core
• New ramjet module, should be much better than the old one
• RAPIER now has slightly improved efficiency

There's something I've been meaning to ask about this - before this update I had my SXT TinyProp engine alternator generating 0.13EC/s at 0% throttle. Now it generates no EC until I throttle up. Is that a new bug or was the prior behavior a bug that was fixed? Given that it's not mentioned here, I think it may be a new bug. I also can't believe it's taken me a month to remember to come here and post about it even tho I've dealt with it on a few flights already! /headdesk

[blowfish]

20 hours ago, JeeF said:

Hey Blowfish!

I've done some diggin around and I couldn't find any specific info about what these entries mean:

https://github.com/KSP-RO/AJE/blob/master/GameData/AJE/Squad.cfg#L92 (till line 111)

Sadly, the CFG isn't commented, nor is the source file. Could you please share what do these mean and how they influence the engines?

Thank you!

I've been meaning to fully document it, but I did write up a post a while back:

 

17 hours ago, Drew Kerman said:

There's something I've been meaning to ask about this - before this update I had my SXT TinyProp engine alternator generating 0.13EC/s at 0% throttle. Now it generates no EC until I throttle up. Is that a new bug or was the prior behavior a bug that was fixed? Given that it's not mentioned here, I think it may be a new bug. I also can't believe it's taken me a month to remember to come here and post about it even tho I've dealt with it on a few flights already! /headdesk

This was due to a change in SolverEngines: https://github.com/KSP-RO/SolverEngines/pull/26 (which I would consider a bugfix).  As it was before the alternator would always output a minimum of 25%, which ends up being very wrong for some engines (mostly on the RF side).  Jets and propellers probably should output some electricity at idle, but it'll take a bit more work to figure out how to make this work correctly for different engine types.

[Drew Kerman]

4 hours ago, blowfish said:

This was due to a change in SolverEngines: https://github.com/KSP-RO/SolverEngines/pull/26 (which I would consider a bugfix).  As it was before the alternator would always output a minimum of 25%, which ends up being very wrong for some engines (mostly on the RF side).  Jets and propellers probably should output some electricity at idle, but it'll take a bit more work to figure out how to make this work correctly for different engine types.

Ah, that would explain why I mixed the fix note. Cool. For now, I'll just install my own "alternator" (KSP generator module) to toggle when I need it

[Calvin_Maclure]

I've seen many people build boats/ships and power them using jet engines that run underwater. Does having AJE installed prevent this since I've tried many different ways of going about it but the engines always always overheat and explode... 

[blowfish]

1 hour ago, Calvin_Maclure said:

I've seen many people build boats/ships and power them using jet engines that run underwater. Does having AJE installed prevent this since I've tried many different ways of going about it but the engines always always overheat and explode... 

With AJE, you will get no thrust underwater.  I was unaware that the engines would explode though.

[Calvin_Maclure]

30 minutes ago, blowfish said:

With AJE, you will get no thrust underwater.  I was unaware that the engines would explode though.

Welp... that would explain it! Any workaround? 

[blowfish]

41 minutes ago, Calvin_Maclure said:

Welp... that would explain it! Any workaround? 

Don't use AJE I guess.  AJE is a realism mod, and that's definitely a situation where jet engines would not work in real life.

Although any engines that don't have AJE configs should do the trick.  I know that there are a bunch of mods I haven't gotten around to adding into AJE yet.

[Bit Fiddler]

I understand this is a nebulous question but here it goes. 

 

Does this increase or decrease the performance of the engines?

 

yes, I know, many factors are involved.  I am just looking for an overall idea.  as in, if I install this will all my aircraft suddenly stop working?

[blowfish]

2 hours ago, Bit Fiddler said:

I understand this is a nebulous question but here it goes. 

Does this increase or decrease the performance of the engines?

yes, I know, many factors are involved.  I am just looking for an overall idea.  as in, if I install this will all my aircraft suddenly stop working?

Well yes it is a complicated question.  I will try to answer it as best as I can.

The first thing to note is that if you are not using FAR you will definitely have issues (if you are, ignore this)

The next thing is that the fuel efficiency (specific impulse) you will see with AJE will be considerably lower than stock.  How much lower depends on which engine and what flight condition you are running at.

Thrust on the runway should be generally the same, but it won't grow quite as much with speed, and might drop off a little bit faster with altitude in the mid-atmosphere.

AJE also introduces temperature limits which puts a cap on the mach number you can run any given engine at (this is separate from stock heating).  So for supersonic planes, you won't be able to fly as fast much of the time.

I hope that gives you some insight.  Let me know if you still have questions!

[Bit Fiddler]

yes... thanks.

iam using FAR so basically at launch it will be mostly the same, then as speeds go up and the air is hotter I loose thrust.   so with this in mind have you, or can we, modify the "precooler"  or other parts in some way to help with this?

 

[blowfish]

3 minutes ago, Bit Fiddler said:

yes... thanks.

iam using FAR so basically at launch it will be mostly the same, then as speeds go up and the air is hotter I loose thrust.   so with this in mind have you, or can we, modify the "precooler"  or other parts in some way to help with this?

All I can say is that the engines will start to overheat in AJE at about the same point they'd overheat in real life.  If there was a realistic way to get around this, someone would have found and built it by now.  The notion of a precooler isn't particularly meaningful as far as real engines go* **

* One might invoke the Reaction Engines SABRE here, but note that in that case the engine cycle is really designed around the precooler and wouldn't function without it.

** It would theoretically be possible to build a more conventional jet engine with a precooler, but you would need a cryogenic fuel like Liquid Methane for it to really have any effect.

[Bit Fiddler]

ah I see.  I figured this pre-cooler part was indeed a real part used in real aircraft.

 

 

[Calvin_Maclure]

18 hours ago, blowfish said:

Don't use AJE I guess.  AJE is a realism mod, and that's definitely a situation where jet engines would not work in real life.

Although any engines that don't have AJE configs should do the trick.  I know that there are a bunch of mods I haven't gotten around to adding into AJE yet.

Dont use AJE?!? Have you gone mad??!

I'll figure something out. But abandon a realism mod??? NEVER!

[Drew Kerman]

6 hours ago, Calvin_Maclure said:

Dont use AJE?!? Have you gone mad??!

I'll figure something out. But abandon a realism mod??? NEVER!

There's really nothing to figure out - AJE won't work underwater and it isn't meant to work underwater therefore when you're playing with crafts underwater just don't use AJE

[Citizen247]

I've been toying with the idea of making models of real jet engine, designed specifically for use with AJE. Especially some older turbojets like the Rolls Royce Nene. I know there's not a great variation in how Jets look, but it would be nice to have them not all using the same model :P. It seems to me that AJE deserves its own models anyway.

[theonegalen]

@Citizen247, you may be the hero we need.

(I'm sorry, I keep flattering you. You just seem to have the skills and knowledge to do the things I wish I could do re: modeling and AJE-configing)

[Drew Kerman]

is this a big deal?

It only happens until around 4% throttle before going positive. I did a searches here for "negative fuel", "fuel flow", etc that didn't turn up anything. A look at the propeller config didn't show anything obviously out of the norm compared to other configs in the file. Pinging @Citizen247 too since he's had experience with propeller configs. I've not modified anything myself, this is with the config for KAX that ships with AJE

I just noticed the Brake Shaft Power reads negative HP as well

Edited May 30, 2017 by Drew Kerman

[Citizen247]

2 hours ago, Drew Kerman said:

It only happens until around 4% throttle before going positive. I did a searches here for "negative fuel", "fuel flow", etc that didn't turn up anything. A look at the propeller config didn't show anything obviously out of the norm compared to other configs in the file.

I've had similar problems with some props I've configured. I can't really remember what the problem was, but I'm fairly sure it was a matter of otherwise seemingly ok settings interacting badly. I ended up getting known good settings from another config and trying to alter them to be closer to the engine I was trying to model without also causing negative thrust/fuel etc. That's pretty vague I know. Hopefully one of the developers who know more about the mods internal workings can shed some more light.

[Drew Kerman]

6 minutes ago, Citizen247 said:

Hopefully one of the developers who know more about the mods internal workings can shed some more light.

well @blowfish has already admitted he doesn't grok the propeller code all that well but hopefully he or @NathanKell can offer some insight