AR-1 - N688G - Pennsylvania

[Abid]

"Rotor Sailing"... OK, who invented this one?

In every helicopter handbook, including the FAA's, the VERTICAL motion of a rotor blade is referred to as BLADE FLAP, while not a single mention of "Rotor Sailing" can be found anywhere other than from these eurotub guys posting on RF discussing why their gyroplanes fail to get off the ground and maintain flight...

And no, it does not matter if the blades are individually hinged at the root or using a teetering, hard-coupled, two-blade rotor design such as found on most gyroplanes. Vertical motion of the rotor blade is still always referred to by the real pros as blade flap, which means Blade Sailing identifies the user as a wanna-be neophyte who doesn't really have a frim grasp on the technical lingo used in rotorcraft discussions. But, hey - cool was morphed into chill...so...why don't we all just update the lay terminology to meet the needs of special interests such as those of American Ranger/ Silverlight, etc?

I dunno. I suppose it can become popular enough to banter about in common chat, much like "eurotub" has been widely recognized as a variety of open-top, wide body tub type semi-enclosed gyroplanes over the years since...well, we all know where that one started.

Which leads one to conclude that this new phenomenon called "Blade Sailing" only occurs on eurotubs, and the rest of us lowly gyronauts scurrying about to get out of the way of the $100k club's TO don't need to concern ourselves with any such newly-invented nonsense, LOL. Maybe this started in India? Or Pakistan? Or wherever...

You guys crack me up. Stay safe and never stop learning how to fly.

Blade Sailing is a term that distinguishes an accident due to retreating blade stall in certain situations from normal flapping that all gyroplanes are doing all the time in forward flight or forward motion. Blade Flap is simply confusing to use to describe an accident. Just because it was used before by gyroplane industry in the US does not mean its the best thing to describe the particular situation. And it is a term used in helicopter engineering tech as well if you read technical papers etc.

Any gyroplane, if you lower the rotor RPM and accelerate too quickly and pass the air through the disc, you are likely to get a retreating blade stall and flip it over. I don't care what model you have. You start rolling with stick not in your gut after pre-rotation but somewhere in the middle or forward, watch out, you are asking for it. This has nothing to do with what the body fairing around the frame looks like.

Eurotub being used as a derogatory term ... well as opposed to what? Camel Erector Set? Nice.
There are plenty of the same accidents in older Camel Erector Set designs as well. They have been flipping gyroplanes and putting them quietly away into their hangers for decades here. Just at Zephyrhills I know of 3 erector sets flipped over on the runway, quietly put away. Chill.

 

[Greg Vos]

In the late 60's I instructed in 2 Young Eagles programs in fixed wing. The first was in a Citabrias teaching basic handling to young cadets at a Military school. The second was an FAA/BATC joint Young Eagle experiment teaching youngsters 10 hrs initial PPL training solely with reference to instruments in 150's. In both cases the object of the exercise was to teach basic handling, and in this case dual controls were obviously necessary.

For any Young Eagle 'introduction to flight' program, the removal of stick and throttle in a rear cockpit tandem machine is I think a very sensible precaution, but probably not quite as important in a side by side.

I can relate that, when a student of mine panicked in an exercise for engine failure below VMC in a Twin Comanche, and instead of reducing the power on the good engine and dropping the nose to increase airspeed to above VMC, and accepting the altitude loss, he slammed on full power and raised the nose. The result was an instantaneous entry into a violent spin. His next reaction was to scream then throw his arms around me and bury his head in my lap. His death grip preventing me from pulling back the fully open throttle.

The Chief Instructor of the school had personally demonstrated to me what to do in the event of an inadvertent spin on my initial approval for twin instruction, and, had promised me that at some stage some student may accidentally do this. All school single engine exercises were consequently required to be done at or above 7,000' AGL. The descent rate in the Twin Com emulating a Catherine Wheel was scary. In the fairly short time it took to break free was around 3,000'.

The student was younger and slighter than I was, but I can say that to break his terrified grip around me, then bring back the power on the good engine and effect a spin recovery, took a massive effort on my part.

The idea of a badly frightened youngster in the back with access to stick/throttle/ignition/radio's can be scary.




It was certainly my impression that the production of a POH for the individual machine one has built, is part of the program.

"Rotor Sailing"... OK, who invented this one?

In every helicopter handbook, including the FAA's, the VERTICAL motion of a rotor blade is referred to as BLADE FLAP, while not a single mention of "Rotor Sailing" can be found anywhere other than from these eurotub guys posting on RF discussing why their gyroplanes fail to get off the ground and maintain flight...

And no, it does not matter if the blades are individually hinged at the root or using a teetering, hard-coupled, two-blade rotor design such as found on most gyroplanes. Vertical motion of the rotor blade is still always referred to by the real pros as blade flap, which means Blade Sailing identifies the user as a wanna-be neophyte who doesn't really have a frim grasp on the technical lingo used in rotorcraft discussions. But, hey - cool was morphed into chill...so...why don't we all just update the lay terminology to meet the needs of special interests such as those of American Ranger/ Silverlight, etc?

I dunno. I suppose it can become popular enough to banter about in common chat, much like "eurotub" has been widely recognized as a variety of open-top, wide body tub type semi-enclosed gyroplanes over the years since...well, we all know where that one started.

Which leads one to conclude that this new phenomenon called "Blade Sailing" only occurs on eurotubs, and the rest of us lowly gyronauts scurrying about to get out of the way of the $100k club's TO don't need to concern ourselves with any such newly-invented nonsense, LOL. Maybe this started in India? Or Pakistan? Or wherever...

You guys crack me up. Stay safe and never stop learning how to fly.

"Rotor Sailing"... OK, who invented this one?

In every helicopter handbook, including the FAA's, the VERTICAL motion of a rotor blade is referred to as BLADE FLAP, while not a single mention of "Rotor Sailing" can be found anywhere other than from these eurotub guys posting on RF discussing why their gyroplanes fail to get off the ground and maintain flight...

And no, it does not matter if the blades are individually hinged at the root or using a teetering, hard-coupled, two-blade rotor design such as found on most gyroplanes. Vertical motion of the rotor blade is still always referred to by the real pros as blade flap, which means Blade Sailing identifies the user as a wanna-be neophyte who doesn't really have a frim grasp on the technical lingo used in rotorcraft discussions. But, hey - cool was morphed into chill...so...why don't we all just update the lay terminology to meet the needs of special interests such as those of American Ranger/ Silverlight, etc?

I dunno. I suppose it can become popular enough to banter about in common chat, much like "eurotub" has been widely recognized as a variety of open-top, wide body tub type semi-enclosed gyroplanes over the years since...well, we all know where that one started.

Which leads one to conclude that this new phenomenon called "Blade Sailing" only occurs on eurotubs, and the rest of us lowly gyronauts scurrying about to get out of the way of the $100k club's TO don't need to concern ourselves with any such newly-invented nonsense, LOL. Maybe this started in India? Or Pakistan? Or wherever...

You guys crack me up. Stay safe and never stop learning how to fly.

https://journals.sagepub.com/doi/abs/10.1243/0954410991533070?journalCode=piga

 

[Abid]

That is great you made your dream of building aircraft here in the US come true! Best country in the world for people to become successful. A bit harder now with the induced inflation, but that should start to go away in about 3 years…

I wanted to fly too when younger, and visited Emery Riddle school back in 81, but they were not placing anyone in jobs at the time. So I went to Penn State University for electrical engineering instead where everyone got jobs when graduated. Had an offer to work for NASA which I turned down for higher paying job. I could have been retired with pension if I took it. What an idiot I was back then! Got my license in an old Cessna 150 flying with hot dogging young instructors building time to become commercial pilots. Man we did crazy things. Lots of spins, flying on taxiway to get to end of runway, direct to end of runway from downwind, etc. All in class D airport too. That was fun. Sounds like IM’s flying…

We had a Champ sell for $25K locally. I talked to the owner and asked him why he is selling it for so little money and he told me it was what he paid for it… Those are the deals you want. Poor old guy…

Good to have you still posting here Abid. Many manufactures and CFIs don’t for whatever reason…

I would have got it at $25k right now. If you find anything like that again, text me immediately

 

[Aerofoam]

"Camel Erector Set"

That's a keeper!

 

[Abid]

That's a keeper!

Yeah not my usual form to use derogatory terms to describe a set of designs concerning their "look and aesthetics" but when on a forum you are seeing a term like "Eurotub" used for years by multiple people to denigrate another "look and aesthetic", well eventually its just annoyingly asking for a punchy response and coming from someone like this latest poster where he even had to mention "Pakistan or India" as a jibe I guess on my ethnicity, well I had to lower my caliber just a bit to handle the mud. Sorry.

P.S. I met first Indian in the US. One became my college roommate and my best man even though they probably got nukes pointed at each other because of dumb arse politicians.

 

[Vance]

I am addressing this mishap because perhaps a third of gyroplane mishaps are rotor mismanagement on takeoff.

I suspect the pilot of N688G knew exactly how he was supposed to pre-rotate and yet he likely had too much indicated air speed for the rotor rpm and stalled the retreating blade.

During his training he was taught many things and most were important.

The need to properly accelerate the rotor before liftoff is apparently easy to imagine “good enough” or what is often call standard deviation by people who use standards.

Different gyroplanes have different pre-rotation techniques and the pilot’s operating handbook is written to keep people as far from trouble as practical.

The Pilot’s Operating Handbook (POH) for your particular gyroplane may approach it in different ways but the basic principles are the same with the goal being reaching flight rotor rpm and flight airspeed without losing control of the rotor.

Keep the rotor away from things until you have aerodynamic control of the rotor (cyclic forward). Aerodynamic control for most rotor systems happens around 80 to 100 rotor rpm.

Once you have aerodynamic control of the rotor the wind may be used to bring the rotor up to speed or some prefer to wait until the rotor rpm is over 200 using the pre-rotator eliminating the step of bringing the rotor up to speed with the wind. This is often done from a stop to keep it simple and yet people still keep damaging gyroplanes no matter how simple it is.

Don’t go to full power until over 180 rotor rpm.

In my opinion there is no magic to it and the principles are well understood.

The easiest way with the leas risk is to follow the POH.

I know some experienced gyroplane pilots who lost sight of these simple principles and standards damaging their aircraft.

I regularly have clients who claim to understand these simple procedures and yet when doing a stop and go; open they open throttle and center the cyclic so the nose doesn’t pop up suddenly. The next move that I prevent them from making is to pull the cyclic back because the nose doesn’t come up and stall the retreating blade because they have too much indicated airspeed for the rotor rpm.

By centering the cyclic they avoid the nose popping up and accelerate faster because we are not putting the energy into accelerating the rotor.

A gyroplane won’t fly without flapping the blades to manage dissymmetry of lift.

 

[Vance]

"Rotor Sailing"... OK, who invented this one?

In every helicopter handbook, including the FAA's, the VERTICAL motion of a rotor blade is referred to as BLADE FLAP, while not a single mention of "Rotor Sailing" can be found anywhere other than from these eurotub guys posting on RF discussing why their gyroplanes fail to get off the ground and maintain flight...

And no, it does not matter if the blades are individually hinged at the root or using a teetering, hard-coupled, two-blade rotor design such as found on most gyroplanes. Vertical motion of the rotor blade is still always referred to by the real pros as blade flap, which means Blade Sailing identifies the user as a wanna-be neophyte who doesn't really have a frim grasp on the technical lingo used in rotorcraft discussions. But, hey - cool was morphed into chill...so...why don't we all just update the lay terminology to meet the needs of special interests such as those of American Ranger/ Silverlight, etc?

I dunno. I suppose it can become popular enough to banter about in common chat, much like "eurotub" has been widely recognized as a variety of open-top, wide body tub type semi-enclosed gyroplanes over the years since...well, we all know where that one started.

Which leads one to conclude that this new phenomenon called "Blade Sailing" only occurs on eurotubs, and the rest of us lowly gyronauts scurrying about to get out of the way of the $100k club's TO don't need to concern ourselves with any such newly-invented nonsense, LOL. Maybe this started in India? Or Pakistan? Or wherever...

You guys crack me up. Stay safe and never stop learning how to fly.

I did not invent the term “blade sailing”. I have come to embrace “blade sailing” to describe a particular type of rotor excursion that appears to me to be responsible for about 30% of gyroplane mishaps and a much larger percentage of gyroplane takeoff mishaps.

I continue to work to find better ways to describe what can go wrong during takeoff and get people to remember not to have too much indicated airspeed for the rotor rpm.

In my opinion a rotorcraft won’t fly forward without flapping the blades to manage dissymmetry of lift.

If there is too much indicated airspeed for the rotor rpm the retreating blade may exceed the critical angle of attack causing it to stall and the advancing blade will continue to provide lift particularly on takeoff.

Some describe this as sailing the advancing blade.

Typically shortly after a blade sailing event the retreating blade will strike some parts on the gyroplane

It is my observation that all models of gyroplanes have had blade sailing events.

Blade sailing is used by some to describe a particular kind of blade flap event and based on the information I have this was just such an event.

 

[Tyger]

Chicken

Ya well... some days you are smart to be a chicken.
I actually had a very challenging flying day yesterday. I went to get 94UL at KGBR, after attending a morning flying-club event and BBQ about 50 miles SW of there. It was rather blustery out of the north all morning but, before I left, I got a forecast for KPSF (a bit to the north of KGBR) of 29010G20. KGBR has runways 11-29, so I thought, "shouldn't be a problem".
I had a couple of "elevator" moments en route. I remember glancing at my vertical speed during one of those, and saw it was at +1900ft/min (while I'm trying to fly straight and level!)
Well, by the time I got to Great Barrington, winds were more like 15G25 and very variable, shifting up to about 340. An airplane CFI who had been instructing landed just before me and told me over the radio to be VERY careful. Well, I'll just say it was more than "interesting". But anyway, I made it down OK, although it wasn't too graceful. I got a compliment, though, from that CFI, who said he was watching, so I guess I'll take it.
On subsequent takeoff, I angled my machine into the crosswind as much as possible. When I pulled the stick back (at 100rrpm), the wind started to blow my whole machine backward. I had to add some throttle just to stay in place, but the rotor spun up to 200 in no time, and I then had a very short take-off roll. Flying NW on the way home, I kept my IAS at around 95mph, but my GPS was showing barely 60mph...
Today is a very similar day. It's brilliant sunshine but there are leaves and branches down all over the roads. So I'm just on my porch, watching the whitecaps on the Hudson river, drink in hand... buck-buck-buck

 

[chrisk]

Ya well... some days you are smart to be a chicken.
I actually had a very challenging flying day yesterday. I went to get 94UL at KGBR, after attending a morning flying-club event and BBQ about 50 miles SW of there. It was rather blustery out of the north all morning but, before I left, I got a forecast for KPSF (a bit to the north of KGBR) of 29010G20. KGBR has runways 11-29, so I thought, "shouldn't be a problem".
I had a couple of "elevator" moments en route. I remember glancing at my vertical speed during one of those, and saw it was at +1900ft/min (while I'm trying to fly straight and level!)
Well, by the time I got to Great Barrington, winds were more like 15G25 and very variable, shifting up to about 340. An airplane CFI who had been instructing landed just before me and told me over the radio to be VERY careful. Well, I'll just say it was more than "interesting". But anyway, I made it down OK, although it wasn't too graceful. I got a compliment, though, from that CFI, who said he was watching, so I guess I'll take it.
On subsequent takeoff, I angled my machine into the crosswind as much as possible. When I pulled the stick back (at 100rrpm), the wind started to blow my whole machine backward. I had to add some throttle just to stay in place, but the rotor spun up to 200 in no time, and I then had a very short take-off roll. Flying NW on the way home, I kept my IAS at around 95mph, but my GPS was showing barely 60mph...
Today is a very similar day. It's brilliant sunshine but there are leaves and branches down all over the roads. So I'm just on my porch, watching the whitecaps on the Hudson river, drink in hand... buck-buck-buck

I first learned to fly at 20N many many years ago. I still remember the wind changes as soon as you got below the tree line.

Also, I would be very cautious of letting the wind push the gyro backwards. Nothing good can come from it and a plenty of bad things can happen

 

[Doug Riley]

Regarding the manual that comes with some kits: My very first encounter with an FAA EMDO inspector when I finished my first Bensen was educational.

He complained about the factory scribe marks on the blades' pitch knuckles -- the ones that allow you to set the blades at Bensen's prescribed pitch. He thought they'd invite fatigue cracking. I said that they were a factory-standard technique.

Yoda-like, he said " Factory? There is no factory. This is a homebuilt. YOU are the factory. We do not recognize anything promulgated by the kit seller as authoritative."

And that's the theory behind homebuilts as far as the FAA is concerned. There is no factory other than you, the builder.

 

[Tyger]

I first learned to fly at 20N many many years ago. I still remember the wind changes as soon as you got below the tree line.

Also, I would be very cautious of letting the wind push the gyro backwards. Nothing good can come from it and a plenty of bad things can happen

I've heard a lot of folks say that the winds have surprised them as they cross the bridge approach from over the river at 20N.
I had no intention of going backward. I was at relatively low engine rpm as I was spinning up the rotor. I simply added a little power.

 

[Tyger]

Eurotub being used as a derogatory term ... well as opposed to what? Camel Erector Set?

I think it's actually just a misspelling / mistranslation. Eurotaube means "european dove" in German.
I'm not sure how you'd back-translate "camel erector set", though...

 

[Sv.grainne]

From Google "Kamelaufrichter-Set".

Could be derogatory depending on how you say it!

 

[Tyger]

I wouldn't want to be called a kamel frichter.

 

[Sv.grainne]

Me either!

 

[Resasi]

Does sound a little sketchy.

 

[N962GT]

https://journals.sagepub.com/doi/abs/10.1243/0954410991533070?journalCode=piga

Thank you kindly for the education, Greg, this is a great reference, at last! Searched but could not find this anywhere. Now I'm on board, understanding the difference between blade flap and sailing.

As to EUROTUB, anyone who thinks it was originally coined this as an intentionally derogatory term is misguided, so here's the background to it: I did a lot of Porsche sports car racing in the '90's. We drivers and builders all referred to a stock 911 body that had been stripped and prepped for the track as a tubbed chassis, or just a tub. Many races were between a small cluster of Corvettes and the rest of us in our "eurotubs", with the 'Vettes faring poorly every time due mainly to superior braking of the 911's.

Unless I am mistaken, Magni and Air Command both started producing open-cockpit, semi-enclosed tandem gyrocopters around the same time during the mid 1990's. Previously thought Air Command was first, but I was mistaken about that and it was Magni that did it first.

Following the success of both makes several other European manufacturers copied the Magni design, including MTO and ELA, and started marketing them in the USA.

I coined the term Eurotub here on RF in the early days of the MTO explosion partly as an affectionate nod to the crossover from my racing days to my new-found hobby flying gyros as a catch-all phrase to differentiate the next-gen group of very expensive rotorcraft from the older, much cheaper Air Commands and Dominators.

Take from it what you will, the term fits the machines intended to a Tee, neatly and succinctly with a bit of flair that rolls off the tongue easily. If you find it offensive, that's on you. The fact that the MTO sellers were often snobbish at Mentone and Bensen Days probably created the cloud of disdain among the "friends in low places" crowd who latched onto "eurotub" quite happily.

Personally, I have never had a bad encounter at a fly-in with anyone piloting a eurotub, and to a man/ woman they have all been wonderfully courteous in every regard. C'est la vie, ma cherie.

 

[BEN S]

He would make outrageous claims like "I invented the Question Mark!"
Dr. Evil.....

 

[N962GT]

He would make outrageous claims like "I invented the Question Mark!"
Dr. Evil.....

Since you seem to be calling me a liar, and since I am always open to being corrected and learning something new, then pray, tell, who came up with "eurotub" before anyone ever read it on one of my previously prolific posts here on RWF under my original handle "NoWingsAttached"?

 

[BEN S]

File this under "Snappy Comebacks I could have said one and a half years ago!"