Other dangers of VDs.

[scott heger]

Good Day Birdy, I have talked to many Rotorcraft CFI’s, both helicopter and gyros, and they all have slightly different techniques for autorotation landings. I remember a factory Bell Helicopter instructor saying he knows 50 ways to land a helicopter, but 49 of them will make you the lead story on the 6 o clock news. I’m sure with your skill level, you know lots of ways to get a gyro to the ground safely that many pilots don’t, nor will ever learn. But that is not what this is about. Every CFI I know, without fail, has taught students to always know the direction of wind while flying , and to get the aircraft nose down to maintain (or gain) airspeed upon a engine failure when near the ground. Downwind landings are to be avoided if possible. Now maybe training is different down under.

Take the below wind conditions from yesterday at my local airport. If the VD was done to stay over a fixed point on the ground while descending; Would you give advice to a weekend gyro pilot to do a vertical decent while pointing south? If the engine failure occurs at 100 feet with a airspeed reading of zero with a dead motor, and he follows the training and pushes the nose over( heading south) he is going to become a high speed dirt-dart in a few seconds. However if he is pointed at the north, and the engine fails, it becomes a routine landing with that much airspeed(it is already reading 30+MPH). Matter of fact, he could “freeze” at the controls and VD all the way in to the ground without any probable damage.




Time Temp. Dew Relative Directon Wind Speed Visibility


16 Jan 6:50 pm 61 2 9 N 12G21 10.00
16 Jan 5:50 pm 61 -5 6 N 16 10.00
16 Jan 4:50 pm 60 -2 8 N 18G24 10.00
16 Jan 3:50 pm 62 1 8 N 17G26 10.00
16 Jan 2:50 pm 64 2 8 N 21G26 10.00
16 Jan 1:50 pm 64 -1 7 N 25G33 10.00
16 Jan 12:50 pm 63 2 8 N 24G32 10.00
16 Jan 11:50 am 63 -4 6 N 25G33 10.00
16 Jan 10:50 am 61 -3 7 N 28G33 10.00
16 Jan 9:50 am 60 -2 8 NNE 25G35 10.00
16 Jan 8:50 am 55 8 15 NNE 24G35 10.00
16 Jan 8:00 am 52 16 24 ENE 16 10.00
16 Jan 7:50 am 51 15 24 E 14G25 10.00
16 Jan 6:50 am 50 17 27 NE 24G30 10.00



Maybe we are just saying the same thing a different way. I always do VD's over a fixed point, does that change the way you think about this?

Hope the weather cools off for you soon.

Scott Heger, Laguan Niguel, Ca N86SH

 

[birdy]

Do you know bout wind gradients Scott?

Never in this thread have i said anythn bout landing with a tail wind.

Wot i'v been onabout has nuthn to do with skill, but readn the wind.
[BTW, i only know one way of landing, the way i do every time]

Would you give advice to a weekend gyro pilot to do a vertical decent while pointing south?
That would depend on the wind gradient.

And another thing, if my engine failed under 100', the last thing i would do is just 'drop the nose', up wind or down.[ experiance has showed me thats not the best thing to do.]

 

[Doug Riley]

Birdy, Scott speaks from the ground frame of reference. You can analyze one of these problems from the frame of reference of Planet Pluto if you want, as long as you define your terms clearly and consistently.

I'm pretty sure Scott means vertical to the ground (a descending "hover"), which may mean 50 mph IAS if it's windy. You're both right from your respective frames of reference, but it's hell on us observers to follow what's going on when definitions keep shifting.

 

[Cobra Doc]

I did a ride-along, as crew chief, for pilot currency in a UH-60. The instructor adivised the pilot to always try to turn into the wind in a power failure. His reason had to do with how fast you are going in, reference to the ground, when you hit the trees. Aerodynamics weren't involved in this particular discussion. I think were were practicing 50 ways to crash a 60 and survive.

 

[pwendell]

Your confusing AS and GS again Scott. If your decending virticaly [ above any wind gradiend], you have no AS. When you drop the nose to regain AS, you'll drop just as far up wind as down wind to reach the same AS. It's only the ground track thats longer in down wind.

Thank you, Birdy, for writing that.

The reason I was always taught to land into the wind, if possible, is because it allows for lower GROUND SPEED at touch down. It also allows for a steeper approach, which can be helpful. It has absolutely nothing to do with AIR SPEED, however, which could care less about the wind direction.

 

[birdy]

Dose anyone ere know anythn bout wind gradients????????

 

[scott heger]

Birdy, a definition....

* A wind gradient describes the change in velocity and/or direction of the wind in a certain direction. There is always a significant wind gradient just above the ground, where the wind gets stronger with increasing altitude. The technique of dynamic soaring allows birds and sailplanes to gain energy from wind gradients. Vertical wind gradients affect starting and landing aircraft: It is part of the reason why airplanes land and take off into the wind. ...

So why is pointing into the wind immediately with a dead motor to land such a bad idea? To answer your question, I never remember any CFI use the term wind gradient in training, and yes I understand the term and the effects on flight.

Airspeed, airspeed airspeed to fly, but groundspeed is what rips you and the aircraft up when you hit, the less the better, thus my posts above.

Scott Heger, Laguna Niguel, Ca N86SH

 

[birdy]

If you read wot i write, you'll know i'v never said anythn bout landing with a tail wind. I'v never done it, so why would i say it can or should be done???

I said approching with a tail wind, solong as the wind hasn't reached ground level yet[ early morning or late afternoon.], you won't be landing with a tail wind.
If your approching[ decending] with a tail wind, the gradient will feed you extra AS the lower you get, finishing with a 0 wind and AS touch down.
Never said nuthn bout landing with a tail wind.
If OTOH, the gradient has reached ground level, the tail wind approch is still best, coz as you near the ground, a simple 180* steady bank will load the rotors and have you touch with the head wind.

So why is pointing into the wind immediately with a dead motor to land such a bad idea?
It depends on your alt at the time the donk dies Scott, but pionting the nose into the wind first means you'v just lost your best oppertunity to load the rotor. If you load it just before touching, you'll have the inertia when you want it, not on the way down.
But with most light machines, anythn above 200' and cruising [ for most pilots] is sufficiant alt to do a compleat 360* turn before landing with no power.
If your cruising into a headwind at 200' and the noise suddenly stops the first thing you gota do is find a spot to put down. And the closer the better. If you drop the nose firstup and [ we will have a situation of clear ground everywhere for the argument], the first thing that happens is the RRPM drops off, and by the time you regain a cumfortable AS, your very close to the ground with slow spinin rotors and not alota AS to spare.
If, on the other hand, you drop the machine into a steep hard bank, you'v plenty of room to do the 360* needed to touch with the wind in your face and plenty of AS and inertia to spare.
But most importantly, if there's any sorta wind gradient happening, a streight dive will have you landing with lower RRPM and lower AS, coz the lower you get, the slower the wind, so the steeper you gota dive.[ further unloading the rotor and loosing more rrpm]
The rip around technique will cancel out the gradient and give you more room too manuver with the extra inertia.

I never remember any CFI use the term wind gradient in training
That don't suprise me one bit. All he's gota do is show you how to get up and back down and end up with a machine that'll fly again. If he had to teach every student everythn bout fly'n, the poor bastered would still be on his first student.

Sorry, i shouldn't av posted that, but the questions were asked.

 

[scott heger]

Ok Birdy, got what you are saying now regarding the 360. I had to do one of these myself on a engine out because I had only trees and swamp infront of me. Just if you already have or maintained airspeed, why would you need to load the rotors for a landing if a good landing area is infront of you? Yes, if your really low, I see the technique working well, but for the average pilot already crapping his pants in a panic because the engine stopped without warning, seems like alot to expect. To me, one thing at a time, make sure you have the airspeed, pick out the possible landing spots and execute the best choice, 1-2-3, keep it simple. I believe, with only a few seconds available, turning around in a 360 looking and deciding where to land is pilot overload, especially if it is the pilots' first engine out experienced. Just a simple difference of opinion here,lots of ways to safely land a gyro.

Scott Heger, Laguna Niguel, Ca N86SH

 

[Doug Riley]

The "rip around" technique does produce results comparable to having a collective pitch control. If your blades have reasonable mass and you crank enough bank at the last moment, you can touch down vertically just like a helo.

The question for instructors is how and where to teach this safely. It's really an advanced, precision maneuver. Blowing it could be quite hazardous -- especially if you sink more than you expected during that last, low bank. I believe a few instructors teach it to newbies, but I don't. I'm happy if they can land smoothly with some regularity with idle power.

We are all haunted by Rod Scamahorn's fatal midair, which happened during such a maneuver. Apparently, his last-minute yank-and-land happened in front of a departing FW ultralight. Three died in the resulting collision. This maneuver can't be done safely with any other landing-departing traffic, except for other gyronauts who know the game (as happens at Bensen Days).

It's a great maneuver for an emergency, or otherwise when traffic allows.

 

[Olbod]

G,day.
couldn't these advanced manouvers be offered as a later training package ?
I dont mean for an endosement but for a relative newbe to increase his
knowledge and skill.
If he had done his basic training and obtained his licence and put on a
hundred or so hours, he could take this advanced training and be shown
the ropes. ?.

 

[Doug Riley]

Advanced training would be great. I'm sure any instructor would be happy to give it. It could cover the "hairpin turn" landing, twirling vertical descents, high-wind fun, test flying and maybe some of the mustering moves.

Still, the problem at the moment is getting people to take any instruction at all. Most want it on the cheap, so you're lucky as an instructor if they stick around long enough to learn how to land in one piece.

I've had people take an hour or two and go home to demolish their (untested) machines. Some instructors require $1,000 up front and/or take the student's rotorblades away (Marion Springer's "tough love" approach).

 

[Olbod]

Doug, I dare say we have a similar problem over here. I dont know the
answer to it but its not good for the Gyro community as a whole.
Do these fools belong to clubs and the like ? If so the club should have the
power to intervene. Also, unlicenced pilots should not be allowed to fly at
Fly-ins etc, unless they are recieving instruction !
Getting tough is probably the only way to kerb it, for the good of all.
Try offering advanced training anyway, I'm sure there would be safety
conscious pilots that would appreciate it and would want to learn more !
Cheers.

PS: What about if you organise holiday groups to come over here to
visit Birdy, and learn a bit about musterin...............
What was that Dave ?

 

[Chopper Reid]

The way I see it Doug is that people just dont have enough respect for a gyro cause they see a gyro as an "simple" flying machine . Of course, too late, they find out that gyros need instruction to fly them.

Just my opinion, while I agree with Birdys engine out technique, we do have to be mindfull that there are many gyros being operated out of very busy airports and in these situations, a landing straight ahead is the correct technique !! [ Just do it right!!! ]

 

[birdy]

As Doug says Rob, they gota lean to fly it first, then as Brian said, respect it for the brainless pice of gear it is.

Maybe then they could go the next step.

Still, theres advanced training and then theres advanced training.
One types for survival, the other is for ....................... wot ever you want to call it.

 

[Doug Riley]

Could Birdy be a tourist draw? I've heard of eco-tourism, and agri-tourism, how about musterin'-tourism?

The mind boggles to think of it...

Here in the U.S., the new Sport Pilot license requires a minimum number of hours of training, like it or not. This contrasts with ultralight flying, in which there is no license: the pilot is on his/her honor to get enough training to stay alive. Many don't bother.

Of course, we still have the related problem that a FW private pilot can fly a single-place Experimental aircarft with no training in type at all. That's really not too different from the ultralight problem. Although the more stable gyros are soemwhat airplane-like (much more so than than the unstable ones), jumping on one and going for it is a recipe for disaster.

 

[brett s]

Odds are better for both you & your machine to survive if you get some instruction on advanced maneuvers, some things just aren't very forgiving.

When I first got my CPL(H) I was already working for an ag operator as a mechanic & was going straight into a pilot job, so I spent 10 hours with a high-time CFI who was also a former ag pilot learning how to stay alive - the nice thing in my case is I needed to burn off a bunch of dual hours to meet the FAA mandated minimum for taking the test so it didn't even cost me anything extra. Best thing I ever did!

Wind gradients can really screw up your day if you aren't paying attention, no doubt about that! One notable occasion for me was when practising autorotations one windy day - passing through about 75' agl I went from 50 kts indicated to around 20. Luckily this was in a Bell 47, lots of rotor inertia was a good thing

 

[Ga6riel]

I think a mustering ticket would be a good draw
but I get the feeling Birdy would bury the rejects in the desert someplace

 

[birdy]

- passing through about 75' agl I went from 50 kts indicated to around 20. Luckily this was in a Bell 47, lots of rotor inertia was a good thing Spoton Brett.
I'm getn the hang of this internet thingy now, its getn easer to tell those who know from those who think they know.

Ga6riel, thered be none of that, coz thered be no takers.