Yeah, I didn't see that other thread in suggestions, but this was the first one I found. I have been working with the jet engines for a while now. I never post on these forums, but I had to come here specifically to post about them. The new specs are crap. Not just the high altitude engines, but the low alt engines too. I like in atmospheric aircraft for Kerbinside science. Now the simplest things require a large investment of time and complexity. I'm fairly experienced with KSP, so I have no problem going in and editing the part stats to where I think they should be. However, I do think that the way they are now may be discouraging to new users. I'm sure Squad has a lot of excel spreadsheets and stats for calculating how powerful they think the parts should be. Here on my thoughts on at least the J-33 though. I feel like a stationary J-33 ought to be able to lift a 10 ton object up to 10k meters vertically. Whatever power it needs to be to do that, it should have it. It is close, it just needs to be tweaked a bit. I feel like it should be able to lift this small VTOL at least a few hundred meters and it cant. One J-33 should give you good performance with every 10 tons of load with the appropriate aircraft layout. Currently it takes me about 1.3 engines per 10 tons which is a bit cumbersome to say the least. It's not like I'm loading these aircraft with fuel, they are largely empty space with maybe 1200 units. I wouldn't mind it so much if we got some 2.5 meter jet engines for heavier aircraft. Right now I'll just make the mods as I need to until there is a fix. It don't think this is too overpowered to ask for, J-33s are only effective on as explorers in two planetary bodies in the solar system. As for the high-alt engines. I don't have too big of an issue with SSTO, but the payloads are meager. Yeah, you can shoot a probe into the sky that'll go all over the Kerbin system, but I don't know. It would be could to at least make the 100t launches somewhat more obtainable.