N975CD MTOsport - Easton, Maryland - 13.10.23

[Vance]

Update - the NTSB Preliminary states

"
The pilot was a former military helicopter pilot and had stopped flying for about 18 years. He
recently returned to flying and decided that a gyroplane was the easiest and most economical
transition. The pilot conducted gyroplane training in the Mt Sport 2017 from a local distributor
(who was also a flight instructor) and then purchased a new gyroplane directly from the
factory. The gyroplane was delivered in September 2023.
Before the pilot took delivery of the gyroplane, he conducted two flights with the flight
instructor/distributor for a total of about 1 hour of dual instruction. The pilot said the gyroplane
flew “beautifully…like a Ferrari.” He took official delivery of the gyroplane and then decided to
fly the gyroplane to his home in Virginia that same day.
The pilot said that before he departed, he performed the abbreviated preflight checklist, which
included checking the flight controls, and found no issues. He then started the gyroplane and
taxied to the active runway, where he performed the before-takeoff checklist. There were no
issues with the flight controls during the taxi or take-off check.
The pilot then departed runway 4. He said he pre-rotated to 200 rpm and the gyroplane began
to roll forward. Once he got “wheel balance”, he increased rpm, and the gyroplane lifted off the
ground. When the gyroplane was about 5 ft above the runway, it made an uncommanded 30°
yaw to the right. He tried to correct with full left pedal, but there was no response. The pilot
said his only option was to reject the takeoff. He reduced power, pushed the nose forward,
then pulled the controls back in an attempt to make a soft landing. The pilot stated that the
main rotor blades flapped, and that he could not recall if the gyroplane then rolled left or right
before it “dropped” vertically about 15-20 ft to the ground. After the gyroplane came to a stop,
the pilot manually turned off the engine.
The pilot did not know why the gyroplane yawed but recalled that the control stick stayed in his
hand, and he felt no feedback in the rudder pedals. He further stated that there were no birds in
the vicinity and the wind was calm.
A postaccident examination of the gyroplane by a Federal Aviation Administration (FAA)
aviation safety inspector found no preaccident discrepancies or mechanical malfunctions that
would have precluded normal operation of the flight controls."

Ref Accident Number: ERA24LA008

I feel there is value in getting gyroplane flight instruction before transitioning to a gyroplane regardless of experience flying other types of aircraft.

I feel more time spent with a good gyroplane flight instructor would have reduced the chances of this accident happening.

Most MTO Sports 2017 I have flown will yaw left on liftoff and roll left when the retreating blade stalls.

The right yaw the accident pilot describes is a mystery to me.

To abort a takeoff takes very little forward pressure on the cyclic to maintain airspeed after reducing throttle in the MTO Sport Model 2017 I have flown depending on how it was trimmed.

Usually learners are amazed at how little drama there is in a gyroplane aborting a takeoff.


From the POH for MTO Sport Model 2017.

4.8 Take-off Procedure for a MTO Sport from the Pilot’s Operating Handbook

Check relative wind

With right hand, maintain control stick in a forward position

Switch pneumatic mode selector to FLIGHT and return to brake with left hand

Hold wheel brake without having locking pawl engaged

While holding wheel brake adjust 2000 RPM with throttle

Activate and hold pre-rotator Vary forward stick position as to avoid lateral forces during prerotation

Let pneumatic clutch fully engage (stabilization at about 100 rotor RPM). If necessary release pre-rotator button momentarily and press again to maintain engine RPM within green arc, respectively to prevent engine from stalling!

Carefully increase engine power to 220 R-RPM – max. 320 R-RPM In case of a slipping clutch (CLUTCH light), continue with less power

Release pre-rotator button

Gently move control stick fully aft (stick travel ~ 1 sec.). In a strong headwind be prepared to stop movement before nose wheel rises!

Release wheel brake with throttle unchanged

Monitor rotor speed and adequately increase throttle to take-off power

In case if a blinking CLUTCH light, consider to abort take-off run.

 

[Mike G]

"Monitor rotor speed" isn't very precise. They could at least have said what you should be looking for whilst monitoring.

Mike G

 

[Sv.grainne]

I just spent about 8 hrs in an MTO 2017 prepping for then doing my practical test over the last several weeks. Right rudder required on takeoff, need to stay in ground effect till 55kts AS. Flyoff, not understanding what happened. Pulling stick back at this point is problematic, perhaps resulting in this crash.

Bobby

 

[Doug Riley]

It seems counter-intuitive but, in practice, I've found that pusher gyros acquire additional rudder authority as they speed up.

I say that this seems counter-intuitive because, in a pusher, the rudder-fin unit is buried in the prop slipstream. On slow gyros, this slipstream's airspeed is about 80 mph. On faster ones, it can be well over 100 mph. At that speed, the rudder OUGHT to have plenty of authority even at zero mph. But....

In the Gyrobee, for example, with very low disk loading, you can lift off around 20 mph, but you'll be flying rather sideways, even with the pedal mashed. Allow it to speed up to around 30, however, and you'll fly coordinated even without the mashed pedal.

Something similar may be happening, although at higher speeds, in the MTO. A behind-the-power-curve takeoff, on top of its other drawbacks, may be plagued by inadequate rudder authority.

A possible culprit in these situations is constriction of the propwash cone. The cone tapers in diameter as you move back form the prop. This is true as long as the slipstream is faster than the free stream (i.e. the gyro's airspeed). At a given prop RPM, the cone tapers the MOST at the lowest airspeeds. It can have a diameter of little more than 50% of the prop's diameter. IOW, you do have fast air over PART of your rudder, but not all of it. Depending on the vertical tail's shape, maybe not much of it. As you speed up, the cone expands and immerses more of the tail in its high-speed air.

Bottom line: don't lift off prematurely by hauling back on the stick or "rotating." That's fixed-wing technique. Fly it off at the speed that the manual (and experienced pilots-in-type) recommend.

 

[Strike]

Ciao Mike
Esattamente. Non ha sbattuto/salpato le pale del rotore. Era dietro la curva con il muso molto alto a piena potenza e ha corretto eccessivamente la tendenza all'imbardata sinistra premendo il pedale destro. Non si è trattato di un'imbardata a destra non comandata. Senza comando imbardava a sinistra a piena potenza e con l'assetto a muso alto.
Ecco perché ho detto con un po' di sarcasmo "Capito" . Sono sicuro che ricorderete da altri poster del forum che volavano con il Magni M24 Plus (motore 915iS) che stavano esaurendo l'input del timone destro durante il decollo e la salita iniziale. Ciò significa che stavano già spingendo completamente il timone a destra e pensavano che ce ne fosse bisogno ancora di più. Non l'hanno fatto. Era semplicemente una pessima tecnica di decollo da parte loro con un atteggiamento a muso alto.

Non lo so subito, ma scommetto che si trattava di una macchina motorizzata Rotax 915iS e questo ragazzo non era pronto a lanciarla in solitaria. Chiaro e semplice.
Scommetto anche che ha più di 70 anni. 18 anni senza volare; puoi scommettere che aveva bisogno dalle 40 alle 60 ore di formazione per essere competente e sicuro. Anche in questo caso si tratta di dure realtà e ci sono sempre delle eccezioni, ma nessuno vuole ascoltare o prestare attenzione, eppure le compagnie di assicurazione lo sanno molto bene. Questa non è nemmeno solo una cosa dell'autogiro, è una cosa dell'aviazione. Se voli per sempre con un 182, puoi stare con un 182, ma se decidi di passare ad un Harmon Rocket a quell'età, avrai problemi simili e quando non volerai nulla per 18 anni... beh, tutte le scommesse sono annullate.

Quindi sì, probabilmente scommetterò con te su questo e prima che qualcuno si avventi su questi 915 sono pericolosi. Non lo sono. Le persone sono pericolose. Impara a volare, correttamente. Trascorri il giusto tempo e non essere arrogante. L'alternativa può metterti 6 piedi sotto terra. Scegliere saggiamente.

PUnfortunately, with such powerful new engines, the possibility of taking off shorter means being left hanging!!! It is always higher, there is so much power that it creates an excessive yaw to the model dangerous if you don't know how to manage it!!! MAYBE NOT EVERYONE IS ABLE TO HAVE CERTAIN MACHINES! EVEN IF THEY HAVE THE MONEY TO GET THEM!

 

[Abid]

It seems counter-intuitive but, in practice, I've found that pusher gyros acquire additional rudder authority as they speed up.

I say that this seems counter-intuitive because, in a pusher, the rudder-fin unit is buried in the prop slipstream. On slow gyros, this slipstream's airspeed is about 80 mph. On faster ones, it can be well over 100 mph. At that speed, the rudder OUGHT to have plenty of authority even at zero mph. But....

In the Gyrobee, for example, with very low disk loading, you can lift off around 20 mph, but you'll be flying rather sideways, even with the pedal mashed. Allow it to speed up to around 30, however, and you'll fly coordinated even without the mashed pedal.

Something similar may be happening, although at higher speeds, in the MTO. A behind-the-power-curve takeoff, on top of its other drawbacks, may be plagued by inadequate rudder authority.

A possible culprit in these situations is constriction of the propwash cone. The cone tapers in diameter as you move back form the prop. This is true as long as the slipstream is faster than the free stream (i.e. the gyro's airspeed). At a given prop RPM, the cone tapers the MOST at the lowest airspeeds. It can have a diameter of little more than 50% of the prop's diameter. IOW, you do have fast air over PART of your rudder, but not all of it. Depending on the vertical tail's shape, maybe not much of it. As you speed up, the cone expands and immerses more of the tail in its high-speed air.

Bottom line: don't lift off prematurely by hauling back on the stick or "rotating." That's fixed-wing technique. Fly it off at the speed that the manual (and experienced pilots-in-type) recommend.

That isn't even proper fixed wing technique. It's a mistake that many high time fixed wing pilots who fly jets and commercial make all the darn time. They have lost their basic stick and rudder feel which is an absolute must to keep your pilot skills up. Otherwise, you are nothing but a replacement of autopilot.

 

[GyrOZprey]

Flying in "underpowered" gyros seems to have been a universally beneficial exercise for new-to-gyro-pilots!

This comment keeps coming up in my interviews with many long time gyro pilots who experienced the power-management of smaller HP engines!

When I learned to fly gyros, the first ones were all in the 100 HP range! managing power available with 2-up on a high DA day is a valuable lesson!

As much as I enjoy the boosted engines on my TAG's with rotax 914 (115hp cruise/125 TO full turbo) Edge kit and the boosted 912( 140 hp full turbo boost) StevePaulet kit ... I still use my power judiciously on the TO roll!

I do think CFI's need to include some training in smaller-HP trainers to teach student pilots better power-management skills ..AND teach GENTLE power application in the machines powered by 140+ HP engines! There is absolutely NO NEED to go for high performance "blast-offs" on EVERY take-off! (especially when newly solo in your 915 powered gyro!)