Why don't aerobatic aircraft have retractable undercarriages?

[Steve888]

I'm starting on some aerobatics soon in a Citabria and was thinking about why most aerobatic aircraft don't have retractable undercarriages.

Of course, some do, but many more don't. I would have thought that, especially for the aircraft used in races like the Red Bull Air Race, not having an undercarriage hanging out would drastically reduce drag and allow them to go faster, or closer to the gates.

On the other hand, the weight impact of the system might outweigh the benefits, or the forces involved preclude holding the gear up during high G maneuvers.

Does anyone else have any other thoughts?

[Pugilistic Animus]

Some crossover models such as a Siai Marcchetti, or ex-mil stuff T-6 Texan...Aerobatics in that sense is barnstorming...it's old, I think some measure of tradition is involved...say nothing of having thinner wings...less complexity less weight...and um....um...other stuff I guess:)

[Intruder]

Weight.

Complexity.

Fixed gear limits max speed, which may be an advantage in many circumstances. At low aerobatic speeds, the drag matters much less.

[Old Smokey]

Most aircraft are purpose built to suit a specific 'mission profile'.

Airliners and 'Touring' aircraft are built for speed, thus most have retractible undercarriage.

Crop Dusters are built for low level manoeuvering where speed is not important (in fact it could be a disadvantage).

'Pure' aerobatic aircraft are built for high manoeuverability, not speed, therefore they typically do not require retractible undercarriage.

Just a few thoughts................. (Good to see a someone from my home town wanting to become a 'complete' pilot):ok:

Good luck in having the greatest fun possible with your pants on!!!:E:E

Regards,

Old Smokey

[grounded27]

Simple, clean is fast. Why not?? Dirty undercarage gains weight, it is a tradeoff.

[NigelOnDraft]

A "pure" aerobatic aircraft does not want to be fast - it wants drag to keep the speed under control on the down-lines. I would say gear is only part of the factor - the RV series of homebuilts are poor aerobatic trainers, in turn due to their low drag (and that's with fixed gear!) and how the speed builds up (to beyond Vne) very easily :eek:

Red Bull is different - they are racing, so yes, retractable might be an advantage, but I suspect their rules have something to say about it.

NoD

[dkz]

The answer is very simple ... WEIGHT !

All the "new" aerobatic planes (Edge 540, MXS, Corvus, Extra 330SC) are as light as possible, all use Carbon-Kevlar to make it even lighter ... to make a landing gear stay in at +/- 10g would need some serious doors/locking mechanism, and that would only make the airplane heavy. The gain in drag is not worth adding so many kilos.

simple :8

[PT6fixer]

In the Redbull Air Race, they actually have a speed restriction as well, so they can´t come in (on the course) throttle to the firewall.
Excellent fun to watch btw.:p

[EW73]

NigelOnDraft...I think your first statement is bang on!

Great for speed control...

EW73