work safe
i'v heard its hard to even get one of these thing off the ground with out cutting the back end off,let alone doing this with one
work safe
I bet that has been smashed to pieces a few times but he can fly that thing.
quote:
Originally posted by OX
i'v heard its hard to even get one of these thing off the ground with out cutting the back end off,let alone doing this with one
work safe
if it had been played backwards the smoke from the engine would allready be there 
There's enough wide open space there, I'd have been stood a lot further back I think .
I have seen dragon flies (the insect) that couldn't fly that well...
D.
Pete...GO TO BED...its, 8:13 my time, that's 1:13 your time....
[Edited on 22/1/05 by white130d]
Having been flying rc helis for around 5 years, I can tell you that that guy can REALLY fly.
The flying is called 3D for obvious reasons,& the manouvers that he was performing are very difficult.
With regards to him flying it very close to himself, I have to say it does look a tad close, but it may be the perspective of the shot. That Raptor 90
is a big model (around 5 feet in length) so it perhaps seems closer than it is !
These machines are very hard to fly.
It probably took me around 3 months just to learn to hover, but with the arrival of simulators you can speed up the learning curve,
quote:
Originally posted by OX
if it had been played backwards the smoke from the engine would allready be there
He needs to get himself a girlfriend
BTW - explain this one to me: I thought helicopters hover by the angle of the rotating blade blowing air downwards, therefore providing uplift. When
then, if he flies it upside down, does it still provide uplift and not just blow itself into the ground ?????
[Edited on 22/1/05 by Jasper]
quote:
Originally posted by Jasper
He needs to get himself a girlfriend
BTW - explain this one to me: I thought helicopters hover by the angle of the rotating blade blowing air downwards, therefore providing uplift. When then, if he flies it upside down, does it still provide uplift and not just blow itself into the ground ?????
[Edited on 22/1/05 by Jasper]
Jasper, it's to do with the throttle setting on the transmitter, you set it to be max when the left stick is in the middle, then blend down to
just over half, then back to max at each end of the travel of the stick.
That's what i was told to do once i got mine passed the hover stage, i havn't yet so it's looking like it's destined for e-bay if
i ever get the time to put it on, one day, one day 
Jason
Jasper
when you first learn to fly you set up the heli so that the main blades always have positive pitch.
When you have the ability to fly 3D you set it up so that at mid stick the blades have zero pitch. At full stick you may have 10 or more degrees of
positive pitch, & at bottom stick you will have roughly the same amount of negative pitch.
So when the heli is inverted you have negative pitch on the blades.
oops, forgot to mention the blade pitch bit as well, a bit important that bit eh !1 D'oh
Jason
Aaaaaah - that explains it, cheers
I am absolutely amazed at the skill of that guy!
He deserves a medal - but then I bet he already has a few of them...
I'm sure the military could find a use for those skills. Imagine a chopper like that fitted with various CCDs feeding back to the operator's
monitor.
What sort of range is achievable with those radio controls?
Rorty
As to range.. on a clear summers day, you can climb a 5' heli straight up vertically, untill it is just a dot . Then keep going untill it
disapears.
At this point the engine is cut to a tickover & negative pitch applied to the blades.
It can then be auto rotated back to the ground still on tickover.
So as you can see range is beyond what the eye can see!
[Edited on 24/1/05 by PaulBuz]
Can you autorotate with negative pitch assuming the airfoil is symetric?
I doubt but you never know...
Cita.
yes, you can.
99% of blades are symetrical
On a gyrocopter the blades are usualy set at zero pitch or slightly negative but their asymetrical airfoil has a positive lift of 2 to 4 degrees at
zero pitch,depending on which airfoil is used.
How does a symetrical airfoil provides lift with a negative pitch setting?
Cita
simply put, it can't.
The negative pitch is only used as the heli is falling to wind up the main blades.
When approaching the ground, the heli is flared to further increase main rotor rpm & kill some of the descent rate.
At this point the energy stored in the rotor is used to land the heli using POSITIVE pitch
I only have experience of the real thing but the flying inverted is very impressive. I normal flight the body hangs underneath the head which is
obviously fairly simple, when inverted the body has to be balanced, I can only compare it to trying to balance an inverted traffic cone on your
forehead. now trying doing that remotely! Only thing I will say is that these models have massive gyros inside which greatly help with the stability;
without then they would be almost immpossible to fly
As for autorotation, the idea is to use the decent of the aircraft to maintain the rotor speed, If you were to go into negative pitch then the blades
would accelerate as it fell and could be disatrous (a real helicopter would pull itself to bits); so the pitch is flattened to only a couple of
degrees and the speed is maintained until you are a neqaring the ground; then pitch is re-applied to 'flare' and halt the decent (I have
been in this situation many times for real when airtesting helicopters and it is quite unnerving)
I realise that with models it may be possible to accelerate the blades withoput too much risk of damage but I would have thought it would still cause
premature failure of the components.
quote:
Originally posted by DaveFJ
(I have been in this situation many times for real when airtesting helicopters and it is quite unnerving)
Oddly enough - yes - For many years
in fact still only live a few miles away......
I know the place from it's refurb job on the roofs, i did alot of the vents
Jason
T'was a fab place to work last summer, watching all the activity on the grass, was difficult to go back to work after each lunch !!
[Edited on 26/1/05 by Deckman001]
dave the gyro has no effect on the cyclic axis' which is what is being used to keep the heli level when inverted.
That said with the advent of modern heading loc gyro's, the tail will stay where you put it & is unaffected by torque reaction.
Incidently the model actually hovers better upside as there is no body to upset the airflow...... thats if you can get your head around left being
right, up being down etc.
This is by far the hardest part of learning to fly a model heli. At least in the real thing, the controls are always the same!!
I thought the function of the gyro was to stabilize the fuselage Paul,if the gyro has no effect on the cyclic axis (for,aft,left,right if i'm correct understanding) why is the gyro in there than?
quote:
...... thats if you can get your head around left being right, up being down etc.
This is by far the hardest part of learning to fly a model heli. At least in the real thing, the controls are always the same!!
If you fly upside down in a real heli and you pull the collective you will get closer to earth instead of getting away of it....i think
quote:
Originally posted by Cita
I thought the function of the gyro was to stabilize the fuselage Paul,if the gyro has no effect on the cyclic axis (for,aft,left,right if i'm correct understanding) why is the gyro in there than?
Cita, the gyro only has an effect on the yaw axis.
, mind you, have only been trying in the back garden which isn't excactly big and has a shed and pond to
avoid I was an engineer - not a pilot, but we did tend to 'have a go' from time to time.....
first time i tried hovering was at about 25feet over a minefiled in Bosnia; concentrates the mind somewhat (BTW I was crap and the pilot had to snatch
control back )
I loved the way they could just hover about 1M off the ground and then taxi out to the runway at same height, was a joy to watch, Was trumped once
though, was working on a B&Q roof down in Yeovil, when a 'bird' appeared over the next roof, when straight over me at about 100ft then
went silent as it went away, later found out it was a cobra, Lovely
Jason
I understand Paul,i thought the gyro had some sort of limited function on the cyclic controle with an overrunning function to help a stable hover.
Have the RC helicopters a governor as well? (engine RPM-pitch)
[Edited on 27/1/05 by Cita]
[Edited on 27/1/05 by Cita]
Yes governers are used by some, but its only quite recently that they have become fit for the job. (speed ...digital servo's etc.)