Didn't know the Skymaster was certified for aerobatics...

This forum has been developed to discuss aviation related topics.

Moderators: ahramin, sky's the limit, sepia, Sulako, lilfssister, North Shore, I WAS Birddog

User avatar
oldtimer
Rank 10
Rank 10
Posts: 2286
Joined: Mon Feb 16, 2004 7:04 pm
Location: Calgary

Re: Didn't know the Skymaster was certified for aerobatics..

Post by oldtimer » Sat Feb 27, 2016 9:18 pm

What happens to the attitude indicator in a roll?
Would you want to enter IMC after some yoyo has been rolling the airplane?
If he has done it once, how many other times has he done this.
If I were in a management position (which I am not) I would have fired his sorry ass out the door immediatly.
---------- ADS -----------
  
The average pilot, despite the somewhat swaggering exterior, is very much capable of such feelings as love, affection, intimacy and caring.
These feelings just don't involve anyone else.

CpnCrunch
Rank 10
Rank 10
Posts: 2926
Joined: Mon Feb 08, 2010 9:38 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by CpnCrunch » Sat Feb 27, 2016 9:44 pm

cgzro wrote:
Also the pre-flight for an aerobatic flight includes a few more items such as loose items checks etc. which likely have never been done in a non aerobatic plane and you risk getting hit in the head by something. I once got a mag-light right in the temple during a low roll and fire extinguishers have been known to come loose.. not fun so careful pre-flight is pretty important. We typically also usually have redundant seat belts because well ... its not pretty when you come loose.
In the video it looks like there's a cellphone and a metal can flying around the cockpit.
---------- ADS -----------
  

co-joe
Rank 11
Rank 11
Posts: 3402
Joined: Mon Feb 16, 2004 2:33 am
Location: YYC 230 degree radial at about 10 DME

Re: Didn't know the Skymaster was certified for aerobatics..

Post by co-joe » Sat Feb 27, 2016 11:37 pm

oldtimer wrote:What happens to the attitude indicator in a roll?
....
Pretty sure that for every roll to the left you do, you have to do one to the right to undo it.
---------- ADS -----------
  

User avatar
trampbike
Rank (9)
Rank (9)
Posts: 1013
Joined: Tue Jun 23, 2009 8:11 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by trampbike » Sun Feb 28, 2016 12:02 am

DanWEC wrote:Why not? Heck didn't Tex Johnson do it in a 707? I'm not an aero pilot, am I naming the wrong type of roll?
As cgzro said, even for an aileron roll you'd need more than 1G to initiate the maneuver and to recover.

Tex Johnson did an aileron roll, which is also what that Skymaster driver did.
An aileron roll is a rotation around the longitudinal axis of the aircraft. Some pitch-up will be required initially for slow rolling machines, otherwise the resulting nose-low attitude after the completion of the roll could be a problem. In a fast rolling aircraft, you can pretty much just use ailerons to complete the roll.

A barrel roll requires a G-loading that is higher than 1G throughout the maneuver (or less than -1 if you want to do it inverted...). The flight path is shaped like a corkscrew. Think of it as the blending of an aileron roll with a loop. You're pulling on the stick while also rolling the aircraft.

Hope this helps.
---------- ADS -----------
  
Think ahead or fall behind!

rigpiggy
Rank 10
Rank 10
Posts: 2321
Joined: Sun Jan 16, 2005 7:17 pm
Location: west to east and west again

Re: Didn't know the Skymaster was certified for aerobatics..

Post by rigpiggy » Sun Feb 28, 2016 4:58 am

There was a paraplegic aerobatic performer used these in the 90s. Steve soper if i recall
---------- ADS -----------
  

cgzro
Rank (9)
Rank (9)
Posts: 1735
Joined: Wed Jul 25, 2007 7:45 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by cgzro » Sun Feb 28, 2016 5:23 am

[quote]What happens to the attitude indicator in a roll? /quote]

If its mechanical/gyroscope based I guess its a bit hard on it. The Extras that have gyro packages come with quick disconnects so you can slide out the gyro instruments prior to aerobatic flight but modern stuff uses solid state gyros which I doubt are harmed by rolling.
---------- ADS -----------
  

goingnowherefast
Rank (9)
Rank (9)
Posts: 1554
Joined: Wed Mar 13, 2013 9:24 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by goingnowherefast » Sun Feb 28, 2016 8:25 am

Go to the 2:00 mark.
https://www.youtube.com/watch?v=jLFwJlPVYyY

Pretty sure these guys aren't Bob Hoover.

Also, from CAR 101.01
"aerobatic manoeuvre means a manoeuvre where a change in the attitude of an aircraft results in a bank angle greater than 60 degrees, an abnormal attitude or an abnormal acceleration not incidental to normal flying"

You aren't going to break the airplane doing a proper roll, but it's still illegal.
---------- ADS -----------
  

digits_
Rank 10
Rank 10
Posts: 2185
Joined: Mon Feb 14, 2011 2:26 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by digits_ » Sun Feb 28, 2016 9:16 am

goingnowherefast wrote:Go to the 2:00 mark.
https://www.youtube.com/watch?v=jLFwJlPVYyY

Pretty sure these guys aren't Bob Hoover.

Also, from CAR 101.01
"aerobatic manoeuvre means a manoeuvre where a change in the attitude of an aircraft results in a bank angle greater than 60 degrees, an abnormal attitude or an abnormal acceleration not incidental to normal flying"

You aren't going to break the airplane doing a proper roll, but it's still illegal.
So if we all start doing loops -and thus redefine 'normal flying'- we will all be legal !
---------- ADS -----------
  

User avatar
redlaser
Rank 3
Rank 3
Posts: 184
Joined: Thu Mar 31, 2011 11:48 am
Location: CYXU

Re: Didn't know the Skymaster was certified for aerobatics..

Post by redlaser » Sun Feb 28, 2016 11:30 am

It boils down to this, aerobatic type aircraft are built to whitstand higher wing loads, whereas Normal or utility aircraft do not, I have see Cessna aircraft come back with bent ailrons after a student pilot or pilot have pushed the structure beyond its limits in doing aerobatic manoeuvres, So before doing a snap.barrel, or ailron roll check your POH to see if any of these manoeuvres are authorised, Normal cat. Aircraft are not.
---------- ADS -----------
  
Don't let your wife talk you out of buying an airplane, :D

DanWEC
Rank (9)
Rank (9)
Posts: 1579
Joined: Sun Jul 26, 2009 1:05 pm
Location: 404

Re: Didn't know the Skymaster was certified for aerobatics..

Post by DanWEC » Sun Feb 28, 2016 2:11 pm

Thanks for the info on the rolls. I was fairly sure I knew the difference between an aileron and barrel roll, but when you hear someone refer to a 1g barrel roll is that just an incorrect term, or loose approximation as opposed to blowing the shit out if it?

So next, is it not feasible for an average pilot to do a roll and stay well within the structural envelope? (Ignoring the contingency g for recovery from a botched maneuver, that's good info btw.)
---------- ADS -----------
  

User avatar
trampbike
Rank (9)
Rank (9)
Posts: 1013
Joined: Tue Jun 23, 2009 8:11 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by trampbike » Sun Feb 28, 2016 2:52 pm

DanWEC wrote:Thanks for the info on the rolls. I was fairly sure I knew the difference between an aileron and barrel roll, but when you hear someone refer to a 1g barrel roll is that just an incorrect term, or loose approximation as opposed to blowing the shit out if it?
Those "1G barrel rolls" are more like "lazy aileron rolls", IMO.
DanWEC wrote:So next, is it not feasible for an average pilot to do a roll and stay well within the structural envelope? (Ignoring the contingency g for recovery from a botched maneuver, that's good info btw.)
It sure is. You're operating out of your aircraft CoA, but it can easily be done (it doesn't mean it should, though!)

Cheers,
Oli
---------- ADS -----------
  
Think ahead or fall behind!

User avatar
PilotDAR
Rank 10
Rank 10
Posts: 2936
Joined: Sun Sep 30, 2012 6:46 pm
Location: Near CNJ4 Orillia, Ontario

Re: Didn't know the Skymaster was certified for aerobatics..

Post by PilotDAR » Sun Feb 28, 2016 4:30 pm

So next, is it not feasible for an average pilot to do a roll and stay well within the structural envelope?
If the pilot has been properly trained, yes.

But, an error in a roll becomes very unsafe quickly. If the axis of the roll becomes downward through pilot inattention, incompetence, or fear, the pilot may well find them self descending inverted toward earth, with speed and G building up quickly. Once in this situation, it's going to end badly. I well flown roll is within the structural limits of a normal category light aircraft. However, a botched roll will exceed these limits. A botched roll probably is within the limits of an aerobatic certified aircraft.

Like many things in piloting, the maneuver itself is basically simple, but the numerous things that can go wrong create the risk, and need for competent training.
---------- ADS -----------
  

cgzro
Rank (9)
Rank (9)
Posts: 1735
Joined: Wed Jul 25, 2007 7:45 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by cgzro » Sun Feb 28, 2016 5:00 pm

So next, is it not feasible for an average pilot to do a roll and stay well within the structural envelope?
In a slow rolling plane odds of success would be poor.
Faster rolling much easier better odds.
---------- ADS -----------
  

User avatar
JasonE
Rank 7
Rank 7
Posts: 545
Joined: Sat Sep 06, 2014 8:26 pm

Re: Didn't know the Skymaster was certified for aerobatics..

Post by JasonE » Sun Feb 28, 2016 5:19 pm

cgzro wrote:
So next, is it not feasible for an average pilot to do a roll and stay well within the structural envelope?
In a slow rolling plane odds of success would be poor.
Faster rolling much easier better odds.
Want to come teach me to roll my Cherokee?? (just kidding, I'm saving for a 2nd acrobatic plane...)
---------- ADS -----------
  
"Carelessness and overconfidence are more dangerous than deliberately accepted risk." -Wilbur Wright

User avatar
CLguy
Rank (9)
Rank (9)
Posts: 1597
Joined: Tue Feb 24, 2004 12:54 pm
Location: Reality!

Re: Didn't know the Skymaster was certified for aerobatics..

Post by CLguy » Sun Feb 28, 2016 5:33 pm

First a 337 cannot be considered as a slow rolling airplane. An aileron roll done properly will put less stress on the airframe than most steep turns and there will be no negative G's or shit floating around the cockpit. I'm willing to bet that there is more stress put on those airframes on a daily basis by those newbies trying to land them in a crosswind. You get too see some crazy shit at times!
---------- ADS -----------
  
You Can Love An Airplane All You Want, But Remember, It Will Never Love You Back!

AuxBatOn
Rank 11
Rank 11
Posts: 3003
Joined: Wed Jan 16, 2008 6:13 pm
Location: North America, sometimes

Re: Didn't know the Skymaster was certified for aerobatics..

Post by AuxBatOn » Sun Feb 28, 2016 5:43 pm

Depends what you define as "slow". Anything less than 180 degrees a second for me is slow.

It's not about stress on the aircraft. It's about certification. The airplane was not certified to do this. It was likely never flight tested. No need to test it yourself...
---------- ADS -----------
  
Going for the deck at corner

AuxBatOn
Rank 11
Rank 11
Posts: 3003
Joined: Wed Jan 16, 2008 6:13 pm
Location: North America, sometimes

Re: Didn't know the Skymaster was certified for aerobatics..

Post by AuxBatOn » Sun Feb 28, 2016 6:06 pm

Just to show the importance of certification for the experts, look here: https://www.youtube.com/watch?v=WMG_G9ostt0 fast forward to 1:45 for the interesting part. If you don't flight test an area of the envelope, you cannot know the behavior of the aircraft in that part of the envelope. An aircraft that was designed for exactly this kind of maneuvers did not behave so well. It lead to a limitation of max 1 roll at full deflection.

What is the 337's behavior while rolling? What are its limitations?
---------- ADS -----------
  
Going for the deck at corner

lownslow
Rank (9)
Rank (9)
Posts: 1160
Joined: Fri Mar 07, 2008 8:56 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by lownslow » Sun Feb 28, 2016 6:47 pm

What does the placard say under the registration? Looks like it starts with "Do not" and I hope it ends with something like "do anything dumb in this airplane."
---------- ADS -----------
  

co-joe
Rank 11
Rank 11
Posts: 3402
Joined: Mon Feb 16, 2004 2:33 am
Location: YYC 230 degree radial at about 10 DME

Re: Didn't know the Skymaster was certified for aerobatics..

Post by co-joe » Sun Feb 28, 2016 7:12 pm

I still say that the manoeuvre voided the c of a until maintenance performs a detailed inspection and signs off on it in the journey log. Not just while it was being performed. Does an overweight landing only void the c of a as the wheels touch and then everything's ok as long as the legs don't fall off? We only saw one roll. Who's to say the first 10 didn't go so well?
---------- ADS -----------
  

User avatar
PilotDAR
Rank 10
Rank 10
Posts: 2936
Joined: Sun Sep 30, 2012 6:46 pm
Location: Near CNJ4 Orillia, Ontario

Re: Didn't know the Skymaster was certified for aerobatics..

Post by PilotDAR » Sun Feb 28, 2016 7:16 pm

It's about certification. The airplane was not certified to do this. It was likely never flight tested.
It's not about getting in, but getting out, particularly if things go wrong. A well flown roll is hardly stressful on a plane, but a recovery can be if the roll was not well flown. If spinning a plane would make you nervous, then so should rolling it. I've posted this before, to remind viewers that certification testing is done to assure that pilots don't have to be test pilots, if they fly within the box.

[youtube]https://www.youtube.com/watch?v=zjB_q7AIvDo[/youtube]

The spin testing went exactly as planned. I temporarily installed a G meter, so I knew what I was doing TO the plane during recovery. I did 2.5 to 2.8 G's at or near Vne, ten times that day. The number which I found un-nerving, and casual aerobat pilots also might, was that each recovery dive at 2.5 G and near Vne, also peaked at more than 9000 FPM down - in a Caravan.

Those who fly certified planes presumably do so to benefit from the confidence that the aircraft has proven itself during certification testing. So why fly it outside those limitations?
---------- ADS -----------
  

cgzro
Rank (9)
Rank (9)
Posts: 1735
Joined: Wed Jul 25, 2007 7:45 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by cgzro » Sun Feb 28, 2016 8:21 pm

Just as an aside, interesting things can happen at full aileron deflection. For example some RVs will exhibit a worrysome aileron buffet if you roll them at full aileron and in fact you need to not use full aileron to get maximum rate im some ac. Also some aircraft need substantial rudder to counteract the adverse yaw of full aileron and that can vary as the speed decreases going up and increases comming back down. Non trivial stuff to do safely every single time.
---------- ADS -----------
  

User avatar
AirFrame
Rank (9)
Rank (9)
Posts: 1933
Joined: Sun Oct 11, 2009 10:27 pm
Location: Sidney, BC
Contact:

Re: Didn't know the Skymaster was certified for aerobatics..

Post by AirFrame » Mon Feb 29, 2016 7:52 am

cgzro wrote:For example some RVs will exhibit a worrysome aileron buffet if you roll them at full aileron and in fact you need to not use full aileron to get maximum rate im some ac.
I haven't measured the exact roll rate, but it feels like the RV-6 rolls faster with the ailerons deflected just short of the point where they start to buffet. The buffeting is also speed dependent... At a slower entry speed you can go to full deflection without getting any buffet.
---------- ADS -----------
  

lownslow
Rank (9)
Rank (9)
Posts: 1160
Joined: Fri Mar 07, 2008 8:56 am

Re: Didn't know the Skymaster was certified for aerobatics..

Post by lownslow » Mon Feb 29, 2016 8:21 am

co-joe wrote:I still say that the manoeuvre voided the c of a until maintenance performs a detailed inspection and signs off on it in the journey log.
Maybe, but what inspection? I doubt the maintenance manual has an inspection for intentional rolls and figuring out exactly what needs to be done is probably as vague a process as figuring out whether or not it was in any way okay in the first place.
---------- ADS -----------
  

LousyFisherman
Rank 7
Rank 7
Posts: 578
Joined: Sat May 10, 2008 8:32 am
Location: CFX2
Contact:

Re: Didn't know the Skymaster was certified for aerobatics..

Post by LousyFisherman » Mon Feb 29, 2016 9:43 am

cgzro wrote:
So next, is it not feasible for an average pilot to do a roll and stay well within the structural envelope?
In a slow rolling plane odds of success would be poor.
Faster rolling much easier better odds.
I'll play the role of average, possibly below average pilot.
I have six hours aerobatics. At the time, 18 months ago I would have been allowed to do solo rolls and loops :) I do not "fly" the roll, I mechanically execute the appropriate procedure for the plane, in this case a Citabria .

Always at least 2000' feet AGL, my choice would be 4000'
Dip 5 degrees to build speed, 120mph if I recall correctly, fairly quick transition to 5 degrees up.
QUICK co-ordinated FULL rudder, FULL aileron, HOLD until just before level again :)
Not slam, but QUICK.

I know I wouldn't want to be there, unexpectedly, below 2000 AGL.
Without the training I wouldn't want to be there at all. Too many distractions.

YMMV
LF
---------- ADS -----------
  
Women and planes have alot in common
Both are expensive, loud, and noisy.
However, when handled properly both respond well and provide great pleasure

User avatar
AirFrame
Rank (9)
Rank (9)
Posts: 1933
Joined: Sun Oct 11, 2009 10:27 pm
Location: Sidney, BC
Contact:

Re: Didn't know the Skymaster was certified for aerobatics..

Post by AirFrame » Tue Mar 01, 2016 8:31 am

Is there a chance that the military's version of the 337 was built/certified differently? Does the military even have many small aircraft that aren't aerobatic?
---------- ADS -----------
  

Post Reply

Return to “General Comments”