Aviation in 1.03

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I'm having a lot of trouble with aviation since the 1.03 update. Just wondering if I'm the only one.

With a basic single-engine plane that worked fine in 1.02 I'm seeing the following:

- I have to move the wings further forward to get lift anywhere near the center of mass.

- Planes used to gently lift off at moderate speeds, but now the only way I can get into the air is by running them off the end of the runway at high speed.

- Once in flight (if I can even get to that point) planes don't want to maintain flight, and SAS doesn't help at all - it just makes the nose bob up and down constantly while losing altitude even faster.

So yeah - I'm not sure if I'm doing something wrong, my install is bugged, or aviation in general has drastically changed.

[Wjolcz]

Showing your design and CoM/CoL placement in SPH would be helpful.

[sal_vager]

Moved to Gameplay Q's btw

[Scoundrel]

Hi! Welcome to the KSP forums. You're not crazy, the aerodynamics and a few parts have changed for the better, which have had the unfortunate side effect of breaking 1.02 and earlier designs. Specifically:

I have to move the wings further forward to get lift anywhere near the center of mass.

Fuel tanks were tweaked and some aerodynamic values were changed.

Planes used to gently lift off at moderate speeds, but now the only way I can get into the air is by running them off the end of the runway at high speed.

Your CoM likely changed due to the change in LF tanks, so you need to shift your aft landing gear closer to the CoM to fix this; alternatively, the lift values have changed, so you need to shift your aft landing gear closer to the CoM to fix this.

Once in flight (if I can even get to that point) planes don't want to maintain flight, and SAS doesn't help at all - it just makes the nose bob up and down constantly while losing altitude even faster.

Without seeing the plane there's no way to diagnose what the source of this problem is.

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Ok, here's an example I just threw together. The two tanks toward the front are empty as it was the only way I could get the CoL far enough forward (not a problem, before this patch). I can only get this airborn by running it off the end of the runway, but at that point it flies reasonably well.

[Arkalius]

- Planes used to gently lift off at moderate speeds, but now the only way I can get into the air is by running them off the end of the runway at high speed.

I've had situations where it seemed like my wheels (or at least the nosewheel) was "stuck" inside the runway and thus I couldn't lift off until going off the end of it. Does the back of your plane bounce up in the air a bit as it spawns on the runway? That's usually a sign this is happening. I'm not sure exactly how to fix it, but I found moving the nose gear around a bit seemed to solve the problem for me when I was having it.

Edited June 24, 2015 by Arkalius

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That actually does seem to help a bit. But in my case it's the nose that bounces up.

[Wjolcz]

Ok, here's an example I just threw together. The two tanks toward the front are empty as it was the only way I could get the CoL far enough forward (not a problem, before this patch). I can only get this airborn by running it off the end of the runway, but at that point it flies reasonably well.

http://i.imgur.com/hL3Qjc6.jpg

Ok, I see what's the problem now. You should put wheels closer to CoM. That way you won't push them into the ground when trying to pitch up. They are just too far back. Just imagine it's a lever and you're trying to push the nose up by bringing the tail down.

Second thing, you should choose a wing type that has pitch controls for you tail. The small fins used in the picture are not steerable.

Edited June 24, 2015 by Veeltch

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Once I was able to get off the ground it became clear that control was pretty lacking. It seems like the current system is a lot less forgiving when it comes to this sort of thing.

Thanks for the help.

[Yakuzi]

Ok, here's an example I just threw together.

Your problem is definitely the placement of the rear landing gear. It should be behind the CoM (closer is better), but in front of your control surfaces. In your current design, the ailerons can't pivot around the rear wheels, instead they're just pushing the plane down on the runway. Moving the rear wheels forward and the ailerons back on the wing should solve your problems.

Also it looks like the plane will be pointing nose down when landed (cant really tell from this angle though). This will make taking off more difficult as well, it's easier with the nose pointing upward.

Have a look at keptins basic aircraft design tutorial for any other airplane info, hints n tips.

[Wjolcz]

Also it looks like the plane will be pointing nose down when landed (cant really tell from this angle though). This will make taking off more difficult as well, it's easier with the nose pointing upward.

Nose pointing down is not a problem if the rear wheels are near CoM. And in that wheel configuration it makes it better to land.

[BlueCanary]

It does seem stall speeds have increased/lift has decreased a lot, from about 30m/s stable flight for a high lift, low mass plane to 40m/s, and with the basic jets nerfed too efficient, slow, short takeoff planes have become really difficult.

Although more fuel in the Mk1 LF tank does help offset the ISP decrease for jets, it more than doubles the weight, compounding the problem.

[eddiew]

The only pitch control surfaces being right next to the CoM aren't helping you any. Tail fins are for pitch, main wings are for roll

Also, don't be afraid of the CoL not being anywhere near the CoM. A CoL behind the CoM doesn't push you into the ground, but rather increases stability.

And you can drain half the fuel for a lighter tank ^^