antbin

http://forum.kerbalspaceprogram.com/threads/117038-Reverse-engineering-Jet-Engines-how-do-velCurve-and-atmCurve-work?highlight=atmCurve

I love spaceplanes, I loved the 1.0 aero, and I'm not going to bother learning 1.0.2. Waiting fingers crossed for the next update to start playing again.

The strakes have seemed very fragile to me. Here's a diff between Type A wings and Big-A strakes part.cfg: Big-A strakes have "heatConductivity = 0.06", which is half the 0.12 default value. They also have "dragAtMaxAoA = 0.6" compared to 0.3 for the Type A wings It's probably the HeatConductivity flag. The Big shuttle Delta wing also has the same half-value heatConductivity, but it's so huge (and fuel filled) that perhaps it doesn't matter?

Another "pony request" - a maximum temperature record (or % of max) for each part, so after an ascent you can inspect the craft to see which part was closest to failing?

Reading through the air intakes: * CircularIntake has emissiveConstant = 0.55 * RamAirIntake has emissiveConstant = 0.7 * intakeShockCone has emissiveConstant = 0.95 Question: Does this affect convection heat from high speed flight? And does it have an effect on how robust the intakes are (besides their 1900-2100C maxtemps)?

mightyhuhn, nice SSTO and nice piloting (lol at gear down mach 5). Two questions: Why the round intakes, and why the pre-cooler?

Nice build! The "canards" look really clean. What are the RAPIERs attached to, precoolers? Do they improve anything? And finally, which parts are the first to explode from over-heating?

Understood! Thanks for sharing your work.

Probably not stall curves, more interested in maximum speed (thrust or thermal limited) and ceiling, in terms of throttle %. For this thread though I'm interested in the intersection of thrust vs. airspeed vs. altitude curves with drag vs. airspeed vs. altitude curves. Both should be computable for level flight and 'typical' aircraft shapes / drag. Gives a ballpark answer to the questions: * How fast / high will it go? * What if I strap a takeoff booster to it to get the RAPIER above Mach 2? * How fast will it overheat and explode?

What tools do you use to capture / plot these values?

Unfortunately Squad missed the chance to make their controls more consistent in 1.0. Another example: IVA camera rotation is still totally different from camera rotation in every other mode. http://forum.kerbalspaceprogram.com/threads/44715-Reduce-of-control-modes-Harmonize-controls-for-better-player-experience

That's what the code says? Why would they go to the trouble of working in Mach numbers if the speed of sound doesn't change with density/altitude? Just for cross-planet conversion? I'd like to start plotting some of these for typical aircraft.

What Cinocal and Hodo said. Also be sure your rear gear are placed dead straight - sometimes the curve of the wing can give them a tiny bit of yaw in angle snap mode.

This is a great mod idea. Can you configure it to only play the audio warnings for the most critical part in the craft? Or to really ask for a lot, an analog sonification (like the back-up camera warning beep in your car?) When flying spaceplanes, I am busy looking at stuff already and visual warnings just add clutter. I can usually figure out which parts are too hot because they're the ones that explode first in test flights. All I want is an audio cue that helps me fly ascents, telling me when (and how much) I should throttle back or pitch up.

Nathan, could you post the math relating altitude to density at the equator? And day/night if you like. Also need the relationship between speed, altitude and mach.

Thanks for the insight Nathan. Pressure and mach make sense, but what pilots could really use is a thrust multiplier chart in terms of m/s and altitude. Does it take many assumptions to recalculate the curves for those measures?

Here's my guess. How to get atmosphericpressure from altitude and mach number from velocity is TBD.

In the code for the new 1.0 jetEngineTurbo.cfg part, we find this: // Jet params atmChangeFlow = True useVelCurve = True useAtmCurve = True machLimit = 2.5 machHeatMult = 6.0 velCurve { key = 0 1 0 0 key = 0.2 0.98 0 0 key = 0.8395604 1.716071 1.051736 1.051736 key = 1.617582 3.022408 1.986082 1.986082 key = 2.327472 4.626338 1.452677 1.452677 key = 3.00 5.3 0.0005786046 0.0005786046 key = 4.25422 2.495532 -4.279616 -4.279616 key = 6 0 -0.02420209 0 } atmCurve { // definite 'kink' to the curve at high altitude, compared to flatter BJE curve key = 0 0 0 0 key = 0.045 0.166 4.304647 4.304647 key = 0.16 0.5 0.5779132 0.5779132 key = 0.5 0.6 0.4809403 0.4809403 key = 1 1 1.013946 0 } Iffn posted a great analysis of the old jet performance, and Ferram chimed in here. Anyone want to take a crack at the same analysis for the 1.0 New Aero?

Nooooooooooooooo! Seriously though, if I'm not mistaken none of these inconsistencies have been ironed out in the past two years, as the user base grows and more people get accustomed to them. I don't blame Squad for not wanting to change, but the sooner the better.

Amazing, I'm blown away.

> you can disable angle snap I have done this once by accident but have no idea how. Help? **edit** Wait, you mean... like part attachment angle snap? That affects gizmos? Oh man, that was not clear at. all. Thanks.

Most engines have 1 or at most 2 degrees of gimbal. But even the fine rotation controls in the SPH / VAB only allow at lesat 5 degrees of rotation. This makes it difficult to perfectly line up engine thrust with the center of mass. It would be very useful to have 1 degree fine controls available in Part Rotation mode. The Part Angle Display 0.30 mod promises this, but doesn't seem to work on node-mounted parts. Any way to do this I'm missing?

This is a usability problem - the R key is so near the WSADQE keys used to rotate pieces in the SPH / VAB, the icon difference is not clear, and it's irreversible. I found this post after having 'tainted' an entire spaceplane with radial symmetry without realizing what I'd done. Had to remove and re-place every piece to get rid of the lingering effects.

Here's an Apollo-style mun orbiter/lander all-in-one for less than 25 tons on the pad. Has enough fuel to do some orbital corrections before landing on the Mun. The re-entry capsule has wings to let you (hopefully) glide right to KSC for a short walk home. >> DOWNLOAD <<

Here's a flight-forgiving try at the Rockets-Only class. There's some fat that could be trimmed from this rocket - while the launch-to-orbit stages are pretty much spot-on, the fuel tanks for trans-Münar burn have some extra left in them after circularizing and adjusting inclination. I accidentally staged (and lost) the leftover fuel after deorbiting the lander (the "M" key is very close to "space"). There's fuel safety margins on both the lander's descent and ascent stages. All told I probably discarded about 55 units of fuel+oxidizer on this run. Kerbal Engineer calls it as 24.97t on the pad (including two hold-down clamps?). Used only stock parts (except Kerbal Engineer for info... does that count?), and carried wings all the way to the Mun and back so as to be able to glide to hit the pad spot-on. If I'm not mistaken that makes: * 2497 points * -150 Stock * -100 No Autopilot/guidance * -50 for Mun Monument * -60 for Launch Pad landing * -40 for RCS docking * -?? for good lookin'? so < 2097 score!