New jet engines help

[Scottiths]

Can someone explain to me exactly what changed with the jet engines? It seems like they lose thrust the higher up I get. Is there a trick to using air breathing engines in an SSTO now that I am not understanding? I can't even get the stock stearwing D45 to orbit anymore (I used to be able to).

Help would be appreciated.

[SkyRender]

The ceiling for jet engines is much more strict in 1.0 and beyond. You can't stick a billion intakes on and expect to be thrusting at full throttle while at the 50km mark any longer. Similarly, you can't reasonably expect to coast at 20km for 2 minutes straight and build up massive speed. Now it's a game of building up as much speed as you can before you start getting into the ultra-thin part of the atmosphere. Specifically, I find that aiming at around 25 degrees above the horizon once you're over about 12km and thrusting at max speed will get the best results. By the time the air thins out too much for the engines to do much, you will have gotten a solid 1000 to 12000m/s speed. As an added bonus, you'll be pointing almost perfectly for the rocket mode change-over as well.

[Reddeyfish]

jet/turbojet/rapier thrust also depends on their airspeed. For example, rapiers are amazing at high speeds, but have trouble breaking the sound barrier to reach their optimal speed.

[Scottiths]

So at around 12k I really can't be using air breathing anymore?

[Reddeyfish]

So at around 12k I really can't be using air breathing anymore?

not with the basic jet engines, no.

Turbojets work fine up to about 18k, and rapiers can go up to about 28k.

[Scottiths]

Ok, awesome. So it sounds like what I want to do is build an SSTO with a combo of Rapier and Turbojets since the Rapier's don't really do a good job of getting up to speed until you already have speed. Is there any easy way to work nuke engines in easily? Or are those days past? Back before 1.0 I would use Turbojets/rapiers to get to orbit and then use the nukes to go elsewhere. I had a Mun ferry that would bring new crew to the mun, but that's kinda changed now

[TheXRuler]

Well, putting in nukes can be kinda hard, I recommend clipping them through an otherwise unused tailsection and adding the other engines radially.

[Mister Dilsby]

Turbojet + nuke works just fine thank you

See this great SSTO thread. for lots of good ideas on how to SSTO in 1.0.2.