VMC Rollover, ever done it?

[avbug]

Perhaps the most poignant reason for not engaging in spins in these aircraft is that they were never demonstrated, nor designed, to be capable of engaging in spins. Someone already mentioned the mass outside of center that contributes to staying in the spin, and resists spin recovery. The bottom line is that these airplanes, most light twins, haven't been shown capable of entering anything more than an incipient spin, and recoverying. Why would you underake the project of experimenting to find out the reason?

 

[jetdriven]

the vmc is at a lower airspeed at higher altitiudes. Which means the airplane stalls first and then Vmc's. Even more dangerous than doing them at 3000 AGL (where you run out of rudder while still flying) , which is recommended in the FTH and the Be-55 baron POH.

Back when I was working on my MEI, I did have the PA-23 Apache start to do a VMC rollover on me. It got to about 60 degree of bank before I got enough rudder authority get control back. Needless to say, that scared the CRAP out of me. I wouldn't want to ever do a full VMC rollover unless I had at least 10,000' and I am not sure if i would really want to.

 

[Propsync]

Didn't enough people die figuring out what the future red line meant?

Don't do it, enough already.

 

[CFIcare]

Unless my memory is just plain wrong, I remember that none of the multi-engine aircraft certified in the last 40+ years have never been tested and certified for spins of any kind.

Again from memory, Piper did some spin test with the then new PA-30 (twin comanche) and found it took in excess of 10000 feet to recover.

Some one with a better memory please correct me if I'm wrong.

----
You are right. I know the guy who spin tested it. In fact, he did a *single engine* spin recovery too. I kid you not. The results of these tests are why subsequent twins were never certified. Why even go there, ya know?

Incidentally, this same guy said that they only thing that scared him worse than that was doing a 20 turn spin...at night.

 

[Rather-B-Flying]

Im not so sure its too smart to do this intentionally. Though Im still in my comercial muli training, everyone Ive talked to said its nothing to mess around with. Back in May 2004 a Seminole from my school went down with 3 souls while doing a Vmc demo. The NTSB investigation is still ongoing, but they believe this is what caused the pilot to loose control. you can read the NTSB report here http://www.ntsb.gov/ntsb/brief.asp?ev_id=20040522X00631&key=1

 

[JAFI]

I don't have the stats handy, but from memory light aircraft multi-training is the most dangerous training you can do. You are taking a "underpowered" aircraft and pushing the limits (climb) on any type of recovery. I am very much opposed to any "observers" in the back seat. With only two people the climb is marginal (if any at all) and with three people the CG moves aft (read flatter spin) and with any engine failure you have 200 lbs more of dead weight to make even less performance and more deadly.

Most turbo props and light jets have a greater SE climb but I would never take either to a full VMC demo.

As I recall, Most light twin training accidents - everyone dies.

My suggestion, Just Say NO.

JAFI

 

[Rather-B-Flying]

Vmc SCARY!

Today I had an experience I hope I never have again.. I was with my instructor in the practice area in a Beechcraft Duchess (twin) doing slow flight (clean)....

Since it is for my commercial certificate, he wanted the better then pts, so he had me fly at the stall warning horn the whole time, after about 5 mins of this we moved on to stalls, steep turns, and then back to slow flight (dirty).

I was under the hood and had no reference to the horizon... I kept pitching up for the stall warning horn, but it never sounded. I kept the airplane between 45-50kts, it didnt feel right but we still had positive performance so i carried on. I kept glancing at my airspeed indicator but it just didnt register at the time but we were WAY below Vso at 65.

My instructor had me initiate a 10 degree bank turn to the right, and then it happened, we rolled over, I wasnt sure what was happening... I just saw my instructor grab both mixtures and bring them to idle cutoff......I fugured something wasn right so I said YOUR CONTROLS! and I threw my hands off the yoke and took off my hood... we were pointed straight down.... He was able to regain control after loosing 1500 ft, luckily we were over 7000 agl when this happened. I attribute the fact that were are still alive to my instructors quick reflexes... and knowing exactly what to to.

Suprisingly there was no panic from either of us... we both reverted to our training, and knew exactly what to do (I let go, and he took control), though he has never done that before. When we got on the ground we checked both stall warning horns..... neither one of them worked, we checked the breaker.. .and it was popped.... it seems while riding the horn durring slow flight earlier we had shorted the system.

 

[KeroseneSnorter]

Today I had an experience I hope I never have again.. I was with my instructor in the practice area in a Beechcraft Duchess (twin) doing slow flight (clean)....

Since it is for my commercial certificate, he wanted the better then pts, so he had me fly at the stall warning horn the whole time, after about 5 mins of this we moved on to stalls, steep turns, and then back to slow flight (dirty).

I was under the hood and had no reference to the horizon... I kept pitching up for the stall warning horn, but it never sounded. I kept the airplane between 45-50kts, it didnt feel right but we still had positive performance so i carried on. I kept glancing at my airspeed indicator but it just didnt register at the time but we were WAY below Vso at 65.

My instructor had me initiate a 10 degree bank turn to the right, and then it happened, we rolled over, I wasnt sure what was happening... I just saw my instructor grab both mixtures and bring them to idle cutoff......I fugured something wasn right so I said YOUR CONTROLS! and I threw my hands off the yoke and took off my hood... we were pointed straight down.... He was able to regain control after loosing 1500 ft, luckily we were over 7000 agl when this happened. I attribute the fact that were are still alive to my instructors quick reflexes... and knowing exactly what to to.

Suprisingly there was no panic from either of us... we both reverted to our training, and knew exactly what to do (I let go, and he took control), though he has never done that before. When we got on the ground we checked both stall warning horns..... neither one of them worked, we checked the breaker.. .and it was popped.... it seems while riding the horn durring slow flight earlier we had shorted the system.

BOTH MIXTURES TO IDLE CUTOFF!!!!!!

Tell me you mistyped that and meant throttles to idle.

 

[Rather-B-Flying]

he brought both mixtures to idle cutoff...... i asked him about this later.. he said he did it as to not fight for control of the throttles with me.......

 

[KeroseneSnorter]

he brought both mixtures to idle cutoff...... i asked him about this later.. he said he did it as to not fight for control of the throttles with me.......

HMMM, my BS detector is beeping.....as in he grabbed the wrong handles in the excitement......but I wasn't there so we will go with his story.

Just as a thought for you from another MEI, generally you should not create a second emergency while correcting the first one, but as I said I was not there and you may be three times his size for all I know, making his ability to overpower your Hulk like grasp on the throttles difficult!

End result worked though..........and that is what counts!


By the way, if you liked the feeling, go take a few aerobatic lessons. Nothing like an hour or so upside down to clear the head!

Now if I can just find that job that will pay for a Pitts, all will be right in my world!!!!

 

[HMR]

he brought both mixtures to idle cutoff...... i asked him about this later.. he said he did it as to not fight for control of the throttles with me.......

How much time does your instructor have in the Duchess? If he was paying attention he would have noticed your unusually low airspeed. It's not that uncommon for that C/B to pop when you're riding it hard. He should have known something wasn't right especially since the Duchess is VERY predictable in its' behavior. Asking you to do a 10 degree turn at that airspeed doesn't make much sense. You were guaranteed to stall. The BE76 has a very pronounced stall buffett before it breaks. Did you notice it?

As for pulling both mixtures... WOW! I've never heard of anyone recommending that for a stall/spin recovery. Sounds to me like he meant to pull the throttles, panicked, pulled the mixtures and then came up with a marginal excuse. Anyone with experience doing airstarts in the Duchess would never shut both motors down.

Be careful out there.

HMR (500hrs BE76 dual given)

 

[Rather-B-Flying]

he is reletively new to the duchess but has alot of seminole time...... i believe he meant to pull the mixtures.... every time we are doing slowflight, stalls, or vmc he has his hand on the mixtures ready to pull.... he is a very competent and through instructor...... but he is a pan am grad.. so who knows... (hahaha)

I believe he was looking for traffic..... it all happened so fast... i believe it was my error in intrepreting... i saw we were really slow... but it just didnt register....

 

[KeroseneSnorter]

he is reletively new to the duchess but has alot of seminole time...... i believe he meant to pull the mixtures.... every time we are doing slowflight, stalls, or vmc he has his hand on the mixtures ready to pull.... he is a very competent and through instructor...... but he is a pan am grad.. so who knows... (hahaha)

Thats a new one on me. When I guard the mixtures it's to make sure the student doesn't pull them....not the other way around.

Been a long time since I instructed, maybe its the hot new instructing technique.

 

[HMR]

...i believe he meant to pull the mixtures.... every time we are doing slowflight, stalls, or vmc he has his hand on the mixtures ready to pull....

Tell him to stop. The only time an instructor would have his hands "ready to pull" the mixtures would be on the takeoff roll. This is just a precaution if the student loses one on the roll and freezes on the throttles, the MEI can shut the good engine down before you veer off the runway. MEI's also use it to "fail" engines on the takeoff roll. This shouldn't be done much faster than 1/2 Vr.

There is NO EXCUSE for this practice during flight. If you were to VMC roll a Duchess the last thing you would want to do is kill both engines. The inboard engine might be your only hope for stopping a spin. This is serious stuff. If you were one of my friends, I'd be sitting down with you and your instructor for a little chat.

 

[Lead Sled]

Tell him to stop. The only time an instructor would have his hands "ready to pull" the mixtures would be on the takeoff roll. There is NO EXCUSE for this practice during flight. If you were to VMC roll a Duchess the last thing you would want to do is kill both engines. The inboard engine might be your only hope for stopping a spin. This is serious stuff. If you were one of my friends, I'd be sitting down with you and your instructor for a little chat.

Rather-B-Flying...
HMR couldn't have said it any better. The next time your CFI has his hands on the mixture controls other than during the initial takeoff roll I'd simply stop the training and return to the airport. Screwing around like that can get you seriously killed. It may be time to have a long hard talk with the chief instructor. That school can't possibly be your only training option. This is serious stuff.

'Sled