B9 Aerospace jet engine

[DC Zhor]

So I've been playing with B9 for quite a while now, basically because I want some extra parts, but after checking their engines I'm at a loss - if someone can explain why this engine is so underpowered, or even redundant...

The D-30F7 turbojet;

I had a plane with the minijet from vanilla for quite a while now, and it could sustain 300m/s while slowly gaining altitude. By the 5 km mark, I would level it, and reach speeds over 400m/s easily.

It weighs 5.924 tons, and has a very simple design, with 40kN of stationary thrust.

Now for the problem plane;

At 18.588 tons, it has foward swept wings (shouldn't matter to KSP though), with 190kN of thrust. So right off the bat, one has significantly more thrust-to-weight ratio than the other.

The issue is, while the small plane has a "service" ceiling of 5 to 6 km, the plane with the mod engine can barely hit 4 km, at 230 m/s, almost begging to stall (this mod engine doesn't have a gimbal).

Has KSP altered the aerodynamics engine to support design characteristics such as wing design? It's been a while since I last played, and for the most part, I used to make some spaceplanes that were essencially biplanes (terrible for speed in real life, still, functioned just fine as SSTOs in the game).

I honestly think this engine is broken. I went so far as to alter the velocity and altitude curves in the code, and it is still lackluster. Any ideas on key values that would make it a bit better but not broken like the RAPIER and the Whiplash? It is supposed to be like the Panther, but as it stands, it is both less efficient and weaker than its vanilla counterpart.

[DC Zhor]

It's definitely not the plane's geometry, tested the Wheesley, and it has better performance.

[Chibbity]

Nothing has changed with the stock game, you'd be better off asking for help on the mod's release page.

[ouro_boros_13]

Maybe the Engine thrust multiplier is laid out so that you have to gain speed at low altitude before the engine kicks in, similar to the rapier

[DC Zhor]

Originally posted by ouro_boros_13:

Maybe the Engine thrust multiplier is laid out so that you have to gain speed at low altitude before the engine kicks in, similar to the rapier

Not really. I made many tests, and learned what the values in the parts' files mean. It's just too low. I can understand the modders not wanting to create something overpowered, but as it stands, the mod's values are underpowered.

I decided to just change them.