The most fuel efficient height and pitch for long flights in atmospheric ships?

[McChubs]

Today I fancied visiting the north pole for an arctic excursion. What I noticed on the way was, unless I angled quite sharply upwards, I\'d rapidly descend. Then, obviously, I\'d ascend up until the engines no longer had the atmospheric throughput they require and dip down to where they did, then go up, fall back down, etc. This strikes me as heavily inefficient, is there a better way? Maybe a more specific pitch using Mechjeb?

[Nomer]

I hate using mechjeb :/

They ruined all the skill this game had.

[vexx32]

Heh. It actually depends heavily on the balance of the plane you\'ve created. The better balance it has, the less you\'ll need to pitch up to stay airborne.

I\'d suggest trying some different designs, balancing them by eye and experimentation. When you\'ve got a balanced flier, then go for the Pole.

And unless you wanna take the fun out of it, stay away from Mechjeb... it makes things far too easy.

[cardgame]

Of course, every plane that I know of needs to stay up at a minimum of 5* at ~13km.

What I did was moderately balance a plane, then use the trim (alt) to keep it mostly level. It varies about a km or so going up and down, but it\'s much better than climbing to 16km and dropping to 10.

[McChubs]

The A.S.S. part of Mechjeb is handy when you\'re a casual player, especially when your designs are wobbly bags of shit. That said, I haven\'t used it at all, I just thought exact pitch choice rather than \'press T, scream and make adjustments\' might be helpful. You think its balance is off? Unless I pitch at something stupid like 30-40 degrees, it\'ll start descending, despite the nose being up.

[Bluejayek]

30-40 degrees sounds like what you would need for a rocket without wings. It seems to me you need more lift on your craft.

As per your question, what you are fighting mainly is drag from the atmosphere. This decreases with height, so just go as high up as you can with your engines still working. For turbojets the cap is near 15km.

[McChubs]

I\'m using two turbojets to carry four FL-T500 cans and three normal jet fuel ones. Is that asking a bit much of them? The extra capacity rocket fuel just seems to last a lot longer, I\'m ignorant of whether they actually implemented jet fuel being more efficient for jet engines?

[Bluejayek]

I\'m using two turbojets to carry four FL-T500 cans and three normal jet fuel ones. Is that asking a bit much of them? The extra capacity rocket fuel just seems to last a lot longer, I\'m ignorant of whether they actually implemented jet fuel being more efficient for jet engines?

All fuel is the same, no efficiency changes. I believe in future versions only jet fuel will work for jet engines and vice versa.

[Markus Reese]

The ASAS makes things easy to maintain pitch. There are a couple way to do long flights. Personally for longer flights, I use the aerospike rockets to do atmospheric hops. I glide up to ~15km with the jet engines, then activate the aerospikes for a quick burn. If you plan on returning, fit two sets of aerospikes if weight allows, I launch and ignite one aerospike to do a high atmospheric hop and jettison when I am coming in for landing. I use my second one to return. That is personal style, but the principles of it makes for nice flying. Also common is to use one aerospike for all maneuvers and glide in to conserve fuel.

For full atmospheric flight, steep pick to a high altitude, then angle myself just a bit above horizon, eventually the plane will reach an equilibrium height and a nice max speed where you can turn down the engines if desired.

[cardgame]

Oh you can maintain a perfectly level pitch, sure, but your TVV may not agree with it...