My synthesis of the recent accident discussions

In recently-built Magni M24s, if the doors are not duly closed, a dashboard warning lamp stays on, but –more important– the rotor revs counter won't work... A very good warning sign, since it's impossible that the pilot may fail to notice that...
You also do not see rrpms indicated if you try spinning up with the rotor brake on...
 
You also do not see rrpms indicated if you try spinning up with the rotor brake on...

Another good idea, but doesn't work that way in my M24. Once, I pre-rotated, took off and flew for a few minutes with the rotor brake on... And the dashboard warning light fully visible...
 
Those are some good ideas to prevent taking off with rotor brake enabled... I also have taken off with rotor brake on with SC M912. I created checklist to triple check its disengaged.
 
Those are some good ideas to prevent taking off with rotor brake enabled... I also have taken off with rotor brake on with SC M912. I created checklist to triple check its disengaged.

There is absolutely no problem in most gyroplanes to fly with the rotor brake on. It does nothing except polish out the brake pad with excess heat. Its not dangerous
 
Another good idea, but doesn't work that way in my M24. Once, I pre-rotated, took off and flew for a few minutes with the rotor brake on... And the dashboard warning light fully visible...
I am a bit surprised the M24 doesn't have that feature... it's fairly easy to do on the M16, just a small switch near the rotor-brake lever.
Warning lights are easy to ignore, but not seeing any rrpm gets your attention fast.
 
How are the canopies under discussion here attached? Hinged at the front, side, rear ?
 
I am a bit surprised the M24 doesn't have that feature... it's fairly easy to do on the M16, just a small switch near the rotor-brake lever.
Warning lights are easy to ignore, but not seeing any rrpm gets your attention fast.
Of course. Without RRPM indication, I wouldn't pre-rotate...
 
How are the canopies under discussion here attached? Hinged at the front, side, rear ?

Ref: AR-1C. Hinges are on the left side (x2 front and back) and latches on the right (x2 front and back but connected together with a rod so they both can be actuated from either seat and from the outside at center). How hard they snatch on latching is adjustable and can be adjusted in the field though its a little tricky access but nothing a mechanic can't handle in 20 minutes
 
As I recall it is hinges on the left side and latch on the right side in an AR1 C.
Thanks, Vance.
I have lots of experience with canopy issues on gliders. Beyond the classic "fly the aircraft " admonition, some planning and thinking through the possibilities, before flight, is useful. On many gliders, if you intentionally fly very slightly uncoordinated with the hinge line into the airstream, it can keep the canopy closed while you sort out your problems and gather your wits.

The most common glider pre-launch checklist follows the alphabet, with Altimeter, Belts, Canopy ....

I had a canopy come loose on me recently (in September) at 13,500 feet and 70 knots in my glider, when a retaining spring on the latch pin had not been reinstalled after maintenance. That canopy has no hinge at all, and comes completely free when you enter or exit the aircraft, so I was in serious danger of losing it completely and having it smash into my all-flying T-tail. Only prior on-the-ground consideration and rehearsal had me prepared to cope and to get down and land safely.
 
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I am a bit surprised the M24 doesn't have that feature... it's fairly easy to do on the M16, just a small switch near the rotor-brake lever.
Warning lights are easy to ignore, but not seeing any rrpm gets your attention fast.
The M24 has a separate rotor brake light. If the light is on, the rotor brake is engaged. And yes, some folks have ignored the warning light. And yes the aircraft flies with the rotor brake engaged. --But the rotor brake may not work very well after you have flown it engaged.
 
Regarding gyro side-slips in general, and not specifically with reference to this accident:

I have long enjoyed (not NEEDED, just enjoyed) slipping gyros. My mentors in the PRA Chapter 24 (Ron Menzie was one) did them in their Bensens way back in the day.

At one little airport that used to host an annual U.L. flyin hereabouts, there was often a gentle cross-wind from a sea breeze. It was possible to do a slow approach in the open-frame Air Command, slipping so that the nose pointed into the wind and across the runway, until you finally kicked around at about 75 feet and landed. In a stronger breeze, it was also fun to fly a small rectangular ground path in the Dominator, with the nose continually pointed into the wind, and the crosswind legs accomplished by slipping first one way, and then the other.

Once, a student of mine, who had FW experience, just about STOOD on one pedal of the Dominator at about 75 mph IAS. I was in the back seat. The roar of wind, sideways past my face and helmet, was impressive.

Please don't try any of this in a gyro with a low-slung open "tub" or enclosed pod body, unless it's been tested and passed for such shenanigans.

None of this slipping nonsense is necessary, of course. In a sport aircraft, however, fun is the mission. I believe that the designer should not tolerate avoidable coffin corners, just as a Pitts Special should not be so designed that you can't recover from a spin. Yes, you could placard the Pitts against spins, then fold your arms after the crash and say "I told you so." Is that really a satisfactory solution, though, in a "play" aircraft?

Proverse slip-roll coupling is not that hard to design out of a gyro. IMHO, this designing-out should be done, and verified by testing.
 
Regarding gyro side-slips in general, and not specifically with reference to this accident:

I have long enjoyed (not NEEDED, just enjoyed) slipping gyros. My mentors in the PRA Chapter 24 (Ron Menzie was one) did them in their Bensens way back in the day.

At one little airport that used to host an annual U.L. flyin hereabouts, there was often a gentle cross-wind from a sea breeze. It was possible to do a slow approach in the open-frame Air Command, slipping so that the nose pointed into the wind and across the runway, until you finally kicked around at about 75 feet and landed. In a stronger breeze, it was also fun to fly a small rectangular ground path in the Dominator, with the nose continually pointed into the wind, and the crosswind legs accomplished by slipping first one way, and then the other.

Once, a student of mine, who had FW experience, just about STOOD on one pedal of the Dominator at about 75 mph IAS. I was in the back seat. The roar of wind, sideways past my face and helmet, was impressive.

Please don't try any of this in a gyro with a low-slung open "tub" or enclosed pod body, unless it's been tested and passed for such shenanigans.

None of this slipping nonsense is necessary, of course. In a sport aircraft, however, fun is the mission. I believe that the designer should not tolerate avoidable coffin corners, just as a Pitts Special should not be so designed that you can't recover from a spin. Yes, you could placard the Pitts against spins, then fold your arms after the crash and say "I told you so." Is that really a satisfactory solution, though, in a "play" aircraft?

Proverse slip-roll coupling is not that hard to design out of a gyro. IMHO, this designing-out should be done, and verified by testing.
Yes you can "slip" a gyro. Keep in mind the concept of center of pressure for the "low-slung open tub or enclosed pod body" Further there may be a low moment of rotational inertia around the longitudinal axis. And there is no stabilizer sticking out the side to counter a roll. Add to this some torque roll. There is an ELA that crashed in Mallorca several years ago and this is the leading theory.

And to quote Doug from some time back "The rotor doesn't care which way it travels. The rotor is circular. It's perfectly happy to fly "sideways" all day as long as the new leading edge is higher in the airstream than the new trailing edge. As with other stability problems in gyros, it's the (casually-designed) fuselage that spoils the happy picture."

So, please do take the warning about slipping seriously.
 
I slipped the SC M912, but it’s all open and made sure the rotor continued to have air through it. Mostly just to better align with landing spot.
 
I slipped the SC M912, but it’s all open and made sure the rotor continued to have air through it. Mostly just to better align with landing spot.

You can surely slip all these gyroplanes. You can do pedal turns with them. You can fly them sideways to a point at lower speeds. You just have to do it with technique. Abrupt movements in the wrong direction are what cause problems. For sure the open cockpit are more forgiving of larger side slips than enclosed gyroplanes but that is to be expected. Stick gyros have no side area to speak of so they are even more forgiving. You try a to quickly start a extreme side slip at 90 mph, that isn't going to be good thing in general.
 
In the early 1960's, the last gasp of the Cierva company built and tested a prototype of a modern, enclosed, cabin-style gyro -- sort of a gyro version of a Cessna 150. It had its problems and never went into production. IIR, the company scrapped the one prototype.

One problem they did wrestle with was this troublesome slip-roll issue. Their solution was precisely to add stabilization surfaces that come into play during a slip. These can take the form of wide mast fairings and/or dorsal fins (though the latter get pretty awkward on a pusher). Back when gyros had wings, pronounced wing dihedral did this job.

As for torque roll, the Cierva folks had dealt with that in the 30's. Immerse the horizontal stab in the propwash and apply differential incidence, or reverse camber on one side. Done. More recently, Aviomania and Little Wing have done the same.

If you don't like the loss of horizontal stability that a short-span immersed H-stab experiences once the throttle is closed, increase the span to get a portion of the stab outside the slipstream. (The slipstream is smaller in diameter than the prop itself except at very high aircraft airspeeds, so this is not that hard. The Dominator has a short, swept H-stab only because it's mounted to the all-flying rudder and needs to stay out of the prop when the ruder is deflected.)

Note the elevated, immersed positions of the H-stabs of the McCulloch J-2 and the Air & Space 18A. An H-stab in the low Magni position just can't do the job of cancelling torque -- i.e. it partially wastes an opportunity to tame the torque roll.
 
Powered parachutes have counter rotating props which eliminates torque effects and also cancels gyroscopic reaction. Perhaps the cancellation of gyroscopic reaction is the primary reason for contra-rotation in parachutes
 
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Powered parachutes have counter rotating props which eliminates torque effects and also cancels gyroscopic reaction. Perhaps the cancellation of gyroscopic reaction is the primary reason for contra-rotation in parachutes
I'm not aware of any counter rotating PPGs except for multiple motor electrics which usually have 4.
 
Yeah this is one time I would disagree with Mr. Beaty and agree with NJpilot. I don't know if you would call it a torque roll or just a tendency for a powered parachute or powered paraglider to turn on climb out or acceleration but it is usually corrected by changing the length of the riser on one side which slightly changes the shape of the wing adding more drag on that side if the riser is shortened or lengthening a riser can take drag out if it was there initially.
Of all the powered paragliders and parachutes I have seen I have yet to see one with counter rotating props.
 
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