CAtegories and Manoeuvres
Joined: May 2006
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From: Londonish
Pet peeve!
Would the 1G mob please go away and think - ANY time you accelerate the aircraft away from a straight path, you are no longer at 1G.
This is what I'd call an aileron roll (Tex)
YouTube - Boeing 707 roll by Test Pilot Tex Johnson
It's a low G manouver. >1 on the pullup, usually <1 but >0 on the inverted section. Why he calls it a barrel roll i'll never know. Simplification for the audience?
This is a BARREL roll. Rather different:
YouTube - T6 Training Video. Barrel Rolls
The defining characteristics as I understand are a large heading displacement and the helical path of the aircraft. Consider it to be rolling the wheels around the inside of a tube (or barrel), hence the name.
In fact, it's almost a loop and a roll combined. I'm usually pulling at least 2.5 through the last part, frequently more, though I'll freely admit that they rank as the single figure I fluff most often (and they're not in the aresti catalog anyway).
Then you have an axial roll where you do NOT pull up; the aircraft travels along a straight, level path whilst rolling; you use top rudder (knife edge), forward stick (-1G), then opposite knife on the way around.
Best though, forget all that and go do flicks/snaps. But definately NOT in the traumahawk
@mad_jock, BackPacker - both right; I'd not be sat in it while somebody looped it, but wet sumps are not uncommon in aerobatic (training) a/c. The robin is wet sumped. The better aerobatic a/c do indeed have inverted oil based on a scavenge system, they also tend to arrange for the engine to continue making noise upside down too! Oh, and the proper name for the 'cup' is a catch tank I think
This is what I'd call an aileron roll (Tex)
YouTube - Boeing 707 roll by Test Pilot Tex Johnson
It's a low G manouver. >1 on the pullup, usually <1 but >0 on the inverted section. Why he calls it a barrel roll i'll never know. Simplification for the audience?
This is a BARREL roll. Rather different:
YouTube - T6 Training Video. Barrel Rolls
The defining characteristics as I understand are a large heading displacement and the helical path of the aircraft. Consider it to be rolling the wheels around the inside of a tube (or barrel), hence the name.
In fact, it's almost a loop and a roll combined. I'm usually pulling at least 2.5 through the last part, frequently more, though I'll freely admit that they rank as the single figure I fluff most often (and they're not in the aresti catalog anyway).
Then you have an axial roll where you do NOT pull up; the aircraft travels along a straight, level path whilst rolling; you use top rudder (knife edge), forward stick (-1G), then opposite knife on the way around.
Best though, forget all that and go do flicks/snaps. But definately NOT in the traumahawk
@mad_jock, BackPacker - both right; I'd not be sat in it while somebody looped it, but wet sumps are not uncommon in aerobatic (training) a/c. The robin is wet sumped. The better aerobatic a/c do indeed have inverted oil based on a scavenge system, they also tend to arrange for the engine to continue making noise upside down too! Oh, and the proper name for the 'cup' is a catch tank I think
Last edited by Mark1234; 16th October 2009 at 23:17.
Joined: Jul 2003
Posts: 1,818
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From: these mist covered mountains are a home now for me.
A Tomahawk simply isn't safe to do those manouevres in (loops, barrel rolls, tailslides, stall turns, or high-G pullups when you stuff them up).
If you want to do it without risking your life (or the life of the next poor pilot who hops in it), then go and do a proper aerobatic course, in a certified aerobatic aircraft.
If you want to do it without risking your life (or the life of the next poor pilot who hops in it), then go and do a proper aerobatic course, in a certified aerobatic aircraft.
Joined: May 2001
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From: 75N 16E
No....But pretty much any aeroplane is capable of aerobatics if done correctly.
There is an excellent video of Bob Hoover demonstrating aeros in a Rockwell Commander 114, for example. There is also a vid of the Eclipse Jet doing aerobatics at a demonstration, not to mention the famous 707 barrel roll.
Not advocating it, just pointing out that it is indeed possible.
There is an excellent video of Bob Hoover demonstrating aeros in a Rockwell Commander 114, for example. There is also a vid of the Eclipse Jet doing aerobatics at a demonstration, not to mention the famous 707 barrel roll.
Not advocating it, just pointing out that it is indeed possible.
Joined: Apr 1999
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From: Glen Prosen, Scotland
G limits
Most light aircraft in the utility category are certified to +4.4/-2 g (ish). It is perfectly possible to fly aerobatics well within these limits, and it doesn't matter whether you have an engine with inverted sytems or not unless you are going to do significant inverted flying e.g. Cessna Aerobats don't. Where it might all go horribly wrong is if you bugger it up, have to pull 6 g or go way past Vne to recover from a botched manoeuvre and the wings decide otherwise - or during the next few flights when someone else is maybe practicing steep turns, since the effects of g on an airframe are cumulative - so it's not the best idea to aerobat non-aerobatic aircraft but it's not impossible or even dangerous if properly done. It's just that there are no margins for error so is it wise? Ahem - you decide. Incidentally the other thing that will get hammered is the engine as the rpm goes way past the red line......
Joined: Dec 1999
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From: Oop North, UK
Incidentally the other thing that will get hammered is the engine as the rpm goes way past the red line......
Joined: May 2006
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From: Londonish
Absolutely NOT advocating aeros in a non certified machine. All sorts of things are possible, if you're very good, and have thought it through carefully. However, people like Bob hoover know exactly what they've got to play with, and have done it all before in aircraft with bigger margins. The have a go heroes make the accident reports.
G limits are even more complex than you may think - the +4.4/-2 DB6 quotes, and even the +6/-4 of the a typical aeros trainer are pitch plane limits. They assume all you do is heave the stick back (or forward). Once you start rolling and pulling G, it's more complex; there are torsional factors, and one side is being accelerated more than the other. Some (few) a/c provide numbers for rolling G, limits. Mostly common practice seems to be to knock 1/3 off - so if it's +6, you don't pull >4 while rolling etc. Personally I try to keep it to less than that..
I would suggest very strongly that aerobatics are something you learn with a good and trustworthy instructor. They are not in themselves particularly difficult, however when things go wrong, they can do so very quickly - A significant part of training is how to escape from botched manouvers. Nearly lost a good friend of mine recently - he flies aeros every weekend, but despite all that, had 'brain fart' when all didn't go as it should - he nearly peeled the wings off, and scared himself half to death.
This sort of forum talk is all well and good, but it's not flight simulator out there, there is no reset button. Anyway, let's face it, most aerobatic aircraft are straight out FAR more fun to fly than their non-aerobatic bretheren.. so why not get into something fun?
G limits are even more complex than you may think - the +4.4/-2 DB6 quotes, and even the +6/-4 of the a typical aeros trainer are pitch plane limits. They assume all you do is heave the stick back (or forward). Once you start rolling and pulling G, it's more complex; there are torsional factors, and one side is being accelerated more than the other. Some (few) a/c provide numbers for rolling G, limits. Mostly common practice seems to be to knock 1/3 off - so if it's +6, you don't pull >4 while rolling etc. Personally I try to keep it to less than that..
I would suggest very strongly that aerobatics are something you learn with a good and trustworthy instructor. They are not in themselves particularly difficult, however when things go wrong, they can do so very quickly - A significant part of training is how to escape from botched manouvers. Nearly lost a good friend of mine recently - he flies aeros every weekend, but despite all that, had 'brain fart' when all didn't go as it should - he nearly peeled the wings off, and scared himself half to death.
This sort of forum talk is all well and good, but it's not flight simulator out there, there is no reset button. Anyway, let's face it, most aerobatic aircraft are straight out FAR more fun to fly than their non-aerobatic bretheren.. so why not get into something fun?
Last edited by Mark1234; 17th October 2009 at 17:00.
Joined: Feb 2007
Posts: 4,598
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From: Amsterdam
G limits are even more complex than you may think - the +4.4/-2 DB6 quotes, and even the +6/-4 of the a typical aeros trainer are pitch plane limits. They assume all you do is heave the stick back (or forward). Once you start rolling and pulling G, it's more complex; there are torsional factors, and one side is being accelerated more than the other. Some (few) a/c provide numbers for rolling G, limits. Mostly common practice seems to be to knock 1/3 off - so if it's +6, you don't pull >4 while rolling etc. Personally I try to keep it to less than that..
Aerobatics is complex stuff and not a Learn-it-Yourself activity. Let alone in a non-aerobatics aircraft.
Joined: Dec 1999
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From: Oop North, UK
A significant part of training is how to escape from botched manouvers.
Joined: Oct 2008
Posts: 399
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From: suffolk
At last we are getting some common sense. People ( my self included when I was young and wet behind the ears) often quote the fact that you can barrel roll anything.
Not many people know what a true barrel roll is, even fewer know that statistically botched barrel rolls kill more people that any other manouvre.
707's have been rolled, Bob Hoover can probably roll anything, but people like him are not normal pilots and they are definately not students.
People like Steve Davis can clear a snooker table in one go and make it look easy, just as Bob makes aeros look easy,but the differance is if Steve fails he may have a red face but thats all.....failure in flying costs lives.
I botched a roll once and blacked out in the recovery, everyone on the ground said it looked spectacular. It scared me to death and I was in an aircraft designed for 9g.
I wish I could do a mind transfer and share that experience on this thread... trust me you would not wish to go there !
Not many people know what a true barrel roll is, even fewer know that statistically botched barrel rolls kill more people that any other manouvre.
707's have been rolled, Bob Hoover can probably roll anything, but people like him are not normal pilots and they are definately not students.
People like Steve Davis can clear a snooker table in one go and make it look easy, just as Bob makes aeros look easy,but the differance is if Steve fails he may have a red face but thats all.....failure in flying costs lives.
I botched a roll once and blacked out in the recovery, everyone on the ground said it looked spectacular. It scared me to death and I was in an aircraft designed for 9g.
I wish I could do a mind transfer and share that experience on this thread... trust me you would not wish to go there !
Joined: May 2001
Posts: 4,729
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From: 75N 16E
I've botched a loop before, and ended up falling from the top......with style 
Also I found the barrel roll exceedingly tricky to do.
Regarding G limits, in a rolling manoeuvre like a BR, the g limits are effectively halved which is why it would be nice to have at least +6/-3G.
Also I found the barrel roll exceedingly tricky to do.Regarding G limits, in a rolling manoeuvre like a BR, the g limits are effectively halved which is why it would be nice to have at least +6/-3G.
