New Tall Tail Question

There may actually be a couple of drawbacks to such a tall mast now that I think about it Tim.

Bob may have trouble flying under powerlines, and such a tall mast might increase the chance of lightning strikes in inclement weather. :rolleyes:
 
I think you should put a 15 foot tall mast on yours Bob. That way you will be assured that you won't take out the rudder, or engine, or flap your blades into the dirt.

And don't worry if anyone tells you not to do it.
Everyone was wrong about the rotor/tail clearance too.

I know you're joking but when you move the major "drag" component (rotor blades) up, does that not mean you have to move everything else because now the center of thrust, ETC. is screwed up?

Who wants to be the test pilot in that contraption?
 
All SARCASM aside , what is wrong with the idea of adding a foot or so to the mast height ?
as far as I can tell nothing.
except the possability of noseing up on throttle up maybe ?
...
surely if you put a 15ft tall mast on the gyro there would be bad reprocussions such as ground handleing but WOULD IT FLY ?
its your statement Gyromike you figure it out !
as Raypierce said what about the moveing of the major portion of the drag further aloft... ?
moveing a portion of the weight that far up would no doubt raise the COG some ... but thats usually looked at as being a good thing is it not ?
...
but seriously 15 feet is a bit more than I had in mind a mear foot would in most cases cure the entire problem.
whats wrong with that idea ?
the benifits are more rotor/tail clearance
raising the COG a small amount
more head clearance when you put a tarp over the rotor blades as a tent <grin>
... the bad things would be a bit easier to tip over while on the ground
more wind resistance
harder to fit in your garadge !
you'll need to strech more to hand start the rotor blades.
....
looks to me although the idea seams silly the PRO's outweigh the CON's here eh ?
the results is a safer gyro all in all isn't it ?
...
and thanks for your vote of confidence TIM but I don't wann'a be the first to fly a gyro with a 15ft mast lets get Gyromike to do it after all its his idea ! <GRIN>
....
for instance TIM what would be the benifits for you to put a taller mast on your KB-2 ? seriously even though you believe you don't need any more rotor /tail clearance you no doubt could benifit from the raised COG eh ?
raising the mast a mear 12inches would no doubt be a large undertakeing but the benifits could well be worth it in your case
....what do you think Tim, is your gyro so perfect that it can't be improved upon ?
Gyromike you have a B8MG very similar to the KB-2 that Tim has
couldn't your gyro benefit from a "SLIGHTLY taller" mast ?
all joking aside its a serious question, and I am sure others have wondered the same thing.
....
Bob.......
 
From what I gather from other threads on this forum, changing the mast height will change the vertical center gravity as well as the thrust line.
 
Bob,
I do plan on raising my mast 6 inches when I put the Rotax 503 on my KB-2. That's to give enough clearance for the larger prop. But, I'm only raising it enough to give the prop about the same clearance my existing prop has now. If you understand the basic flight characteristics you'll know this is plenty of clearance.
 
Jeff, the thrustline only chages when the engine mount height or angle is changed.

Tim, by the time you get all the pieces at your hangar, you can build another one. I have more aluminum, if you want some for an axle, let me know.

Bob, I've been the test pilot on a number of setups. Some, I've had a stiff drink after, and some I should have had the drink before!

Phil.
 
Just for the heck of it I checked the dominator tonight when I was cleaning the blades. If the gyro is on the tail wheel, and you pull the blades ALL THE WAY BACK, they do touch the ground, and clear the tail by about 4-5 inches, PLENTY PLENTY of clearance on both accounts, I have never heard of a dominator hitting it's own tail, or the rotors hitting the ground,
So, for what it is worth, there you go.
 
Guys,

There is a simple way to solve Bob's concern.

Add 1 foot above the rotor head. Then add wires from each rotor blade about 2/3 from the tip of the rotor.

By doing it this way the blades will be support out past the tail. :sorry:

Only problem I see is the wire might sing as they rotate. But that will be a good thing. You won't be able to hear all the other guys laughing as you go by. :rolleyes:

Here is a picture of what I thinking. Notice the top wire braces.


Just having a little fun.

Leon

(kc0iv)
 

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thanks Jeff
I can't see how raising the mast would effect the thrust line
because the thrust line is simply he placement of the prop...
...
lets Imagen a Benson gyro, take the mast off and replace it with a mast that is 12" longer... leave the engine , prop, wheels rudder and everything else alone except the control rods and perhaps the pre rotator....of course
the only effect I can see that this action would have on the flying ability of the Benson gyro is perhaps (and I do mean that as I am guessing here ), a increase of the lead lag time in your control input...another words a fraction longer before your inputs are realized by the craft...
there may be a bit of nose up at throttle up but I seriously doubt that because we didn't move the rotor that far...
....
so as close as I can tell there would be NO appreciable difference...
yet the craft would theoretically be a safer machine.

...

I don't know of any reasons to have a mast as short as possable
on a gyro, although I am SURE there are some reasons for it as having a short mast is quite common,
perhaps its just because of the ease of storage I dunno.
....
but if storage is the only Reason to have a short mast and we risk a higher percentage of chances of takeing out the tail section of out gyros when we fly because of it I say "GOOD GREEF WHY ? "

make a folding mast if you must but get a taller mast on the thing ! ...

Seriously I bet a more learned person than myself could calculate the chances of the rotor comeing in contact with the tail and equate it into hours of flight time... it happens often enough to be a killer of our pilots, if thats all it is why don't we change it ?
.....
Bob.......
 
thats an idea Leon ! but the rotor blades are supposed to flap to a certain extent ! you would be stiffening them up a great deal by doing that.
if you could guy-wire them up and still alow them to pivot on the teeter bolt, who knows it might well keep the rotor out of the tail... I'ed worry about the drag of the cables myself...
it'ed probly slow the rotors way down !
it wouldn't be my first choice.... but it is an idea !<grin>
....
Bob......
 
thank You Scott for that observation !
we all Know that Rotor/tail contact is RARE ...But it happens often enough to make you set up and take notice... when it does its a killer.
I feel we are gambling with our lives because of the design of our gyros, when we can reduce the risks even more, thats all !
if mathematical figures were available we'd probably see something like 1 in every 6000 hours of flight time eats the tail feathers...now weather that is because of a bunt over or zero g maneuver is something else to consider... but the end results is the craft falling out of the sky
now I am just taking a wild guess at the statistics here, I really have no idea. but considering how many hours are flown each year there is usually 2 or 3 deaths per year in the USA alone in gyros
... those deaths are of course for a variety of reasons. but if we can eliminate just ONE of those deaths by making the gyros safer it would be an endeavor well worth while , don't you think ?
and we certainly won't make the changes necessary as long as people think their gyro is perfectly safe the way it is .
....
Bob.....
 
"Seriously I bet a more learned person than myself could calculate the chances of the rotor comeing in contact with the tail and equate it into hours of flight time... it happens often enough to be a killer of our pilots, if thats all it is why don't we change it ?"

Do you not understand Bob that these pilots had flapped their blades out of control or PPO,d and would have crashed whether they took out their tail or not?

I know I should just drop off this thread like people smarter than me that simply have given up on you Bob but that just seems to convince you that you have it right, and may cause people that are trying to learn something also think you are right.

I am not dissin you Bob (no emoticon for sincerety)
 
Bob, damn it i tried to stay the hell out of this one but i got to back up Mr61.
Bob i used to fly an ultra hTL Air Comand, normally they have a 60" prop, but i put a 68" on it, and to do that i raised the motor, but the rest of the frame was the same, OK, now as most people would know that if you spun the blades and an AC with the stick back sitting on the tail wheel, they would dig in the ground and probably take the tail off, YET and are you reading this YET i was able to countless times land with the nose pointing to the sky and not touch the ground, Bob your good value but you dont understand **** about gyros, give your frien and mine Sonny J a ring and ask him if i know what im talking about, it is one THINK to know you know some thing but it is a completly different thing to KNOW you know nothing.
 
Raising the mast won't change the response time on controll inputs.

It will change the CG to thrustline offset as well as the weight distribution on the mains, I.E. the rock back. It will also increase the drag of the airframe. It will also increase the weight of the airframe. It will also increase the hazards of hand starting the blades. It will also increase the storage space needed for the airframe.

Phil.
 
Haven't you guys read his disclaimer under his posts? Your wasting your time....
 
Bob,
Maybe you should consider staying on the ground? That way you would be safe from all the danger of flying and flapping.
 
Bob, Go back and read post #28 in this thread. It explains blade flapping. You still do not understand what causes blades to flap. A person doesn't fly along, hit some turbulent air and have the blades take off the tail. If the blades flapped the way you think, an extra 12" height on the mast would not make any difference.
 
Just my small observation, I checked this same senerio out on the new 07factory built Sparrowhawk that I am training in and when stick is all the way back and on the teeter stop the Rotor blade comes down about 8 inches below the top of the tail. This is the way they come from the factory.
 
What??

What??

Bob,
Maybe you should consider staying on the ground? That way you would be safe from all the danger of flying and flapping.

Bud that is a no go too.

Many people drive automobiles up and down highways going head on at each other in opposite directions at speeds reaching 55mph (or more) towards each other albeit in lanes separated by a three or four inch paint stripe that is mere inches!!!!!!

Women and children are exposed too.
 
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