Aerobatism...

[machineman9]

Being bored in a school holiday I decided to look on avbuyer and other sites for interesting aircraft that one day I may own, or something like that.

Anywho, on some aircraft it says 'full aerobatic' and I think sometimes it says 'half/partly aerobatic'

Now, I know what aerobatics are, but what is the difference between the terms? I am taking a guess at saying it is different manouvers that they can do, but what like? What seperates them?

Cheers

[EGNX]

I'm guessing if an aircraft is "Fully Aerobatic" then it can do pretty much what you want... Where as if it is "Partially Aerobatic" then there may be only a few aerobatic manouevers that it is capable to do...

I know for the Viking gliders we are only allowed to do loops and chandelles and occasionally spins and every thing else is off limits... I'm not sure if this is because the aircraft simply can't do the manouevers, like loops, or it's because it would be putting too much stress on the aircraft and could be taking it out of limits.

[C]

I think the main difference is the aerobatic capability.

For example, compare the C152 Aerobat against the Grob 115E Tutor. The Cessna, despite its name, would almost certainly fall into the "semi-aerobatic" category. It is capable of the basics, and maybe a little more. The Tutor is effectively fully aerobatic, being capable of almost any manouvre.

However, I suspect that the goalposts have been shifted slightly with the development of competition aerobatic aircraft of the last 30 years.

[machineman9]

Ah right. Yeh, the wings would snap on most gliders if they do certain stunts, they are so long they would bend too far and break off- though I have seen stunt gliders and they are bloomin crazy  ;D

So is there any real sort of list of capabilities? Maybe it is down to how effectively they can do the stunts.

I hear the aerobat is quite a good aircraft to fly too. Good trainer (along with the 172) and a few tricks in its books... but the Tutor is much nicer to throw around the sky.

[Boss_BlueAngels]

As far as the airframe is concerned, the difference between full and partial aerobatics also has to do with configuration such as inverted fuel systems.  The Decathlon is a fully aerobatic aircraft as it is capable of outside (negative G) maneuvers as well as inside (positive G) due to its inverted fuel and oil system.  In fact, I can fly the Decathlon for up to 2 minutes inverted.  Airplanes such as the Aerobat (Cessna 152) and Citabria, however, are partially aerobatic as they do NOT have inverted fuel/oil systems.

[machineman9]

Ah right. So is this right? They can go inverted, but not for very long or else their fuel supply will be cut-out because it cant get fed.

[Chris_F]

Ah right. So is this right? They can go inverted, but not for very long or else their fuel supply will be cut-out because it cant get fed.

I'd be more concerned about what happens to all that oil, and all those rotating parts that immediately get starved of it.

[machineman9]

Ah right. So is this right? They can go inverted, but not for very long or else their fuel supply will be cut-out because it cant get fed.

I'd be more concerned about what happens to all that oil, and all those rotating parts that immediately get starved of it.

But its that principle isnt it? The engine and parts are getting starved of the fluids they require to work.

[DaveSims]

Depends on whether or not the airplane has inverted fuel and oil systems.  If it has those the engine will remain running just fine.

[Chris_F]

Ah right. So is this right? They can go inverted, but not for very long or else their fuel supply will be cut-out because it cant get fed.

I'd be more concerned about what happens to all that oil, and all those rotating parts that immediately get starved of it.

But its that principle isnt it? The engine and parts are getting starved of the fluids they require to work.

Right.  As long as you pull positive G's (fly upright or do a loop with enough load to keep the G's positive, etc) then everything's just fine.  In theory if you unload to 0 or negative G's then the engine gets starved of fuel or oil.  Don't know if all airplane engines are dry sump, but if they aren't then it could be pretty catestrophic as oil attempts to pool on the bottom of very fast moving pistons... probably resulting in a loud BANG followed by eerie silence.  :)