??????????

[birdy]

I'v also posted this on the yank forum, coz i like to know wots go'n on.A simple question to those who have a thorough understanding of rotors.The other day, while geting a bit hot under the coller at work, i found myself in a sticky spot.At bout 40pmh and 5' off the ground, i was confounted by a tree, a big tree that was too close[ only 20' ahead] and too high [20' above me] to get over.It was also a little too wide to duck around in the normal fashon without some serious trimming happening.Instinctivly, i chopped power and [ quite volently] heaved the stick left and back. Much harder than i would normaly, coz normaly i'v got a bit more room to move.The machine basicaly stoped instantly and with the aid of some rudder, was pointing away from the tree. With the reapplication of full throttle and holding the stick back, i staggered to safty, missing the tree and stayn off the ground. IOW, a right angle turn on the spot and without any alt loss. [ says sumthn for gyros ay][]The only thing that concerned me was a loud and distincet 'chopping' sound.As i was 'staggering' away to safty, i looked back, expecting to see part or all of my rudder missing, coz thats wot it sounded like. It sounded like a rotor chopping at a plywood rudder.[ bout 5 or 6 chops]Knowing now that it wasn't the rudder getn trimmed, and i know i missed the tree[ allbe it not by much], and theres no other evedence of anythn hitting the rudder or rotor, i'm wundern wot made the noise.?????Was thinkn maybe sumthn to do with the blades airodynamicaly, like a partial stall [ huge cyclic demands]or maybe this new 912 don't like such abrupt full power changes and pinged or sumthn.?????It don't realy matter, coz i'm still alive and i'm not plan'n on do'n that sorta move any time again soon, but if i knew wot made the noise, and it was nuthn detremental, then with a bit of practice, it could become a handy move in my line o work, if you get my drift.[]Ignorance is bliss............but only till you realise you were.birdy, here.

[NiqueNaque]

Birdman,You've got marvellous reflexes...Blades in the grass?? Any marks on the leading edges?Though I know not of what you speak, I know of another syndrome, it used to happen to me on motor bikes, I used to call it the 50 hour syndrome. Just when I was getting comfortable within the first 50 hours on the thing, that was when the bugger would throw me.. my own stupid complacency. I know you can't afford to be complacent and wouldn't be, but it is something to watch with your 'new' ferel.Cheers,Nicholas TomlinAlarmist - www.alarmist.com.au - we scare for you

[NiqueNaque]

Birdman,You've got marvellous reflexes...Blades in the grass?? Any marks on the leading edges?Though I know not of what you speak, I know of another syndrome, it used to happen to me on motor bikes, I used to call it the 50 hour syndrome. Just when I was getting comfortable within the first 50 hours on the thing, that was when the bugger would throw me.. my own stupid complacency. I know you can't afford to be complacent and wouldn't be, but it is something to watch with your 'new' ferel.Cheers,Nicholas TomlinAlarmist - www.alarmist.com.au - we scare for you

[NiqueNaque]

Birdman,You've got marvellous reflexes...Blades in the grass?? Any marks on the leading edges?Though I know not of what you speak, I know of another syndrome, it used to happen to me on motor bikes, I used to call it the 50 hour syndrome. Just when I was getting comfortable within the first 50 hours on the thing, that was when the bugger would throw me.. my own stupid complacency. I know you can't afford to be complacent and wouldn't be, but it is something to watch with your 'new' ferel.Cheers,Nicholas TomlinAlarmist - www.alarmist.com.au - we scare for you

[NiqueNaque]

Birdman,You've got marvellous reflexes...Blades in the grass?? Any marks on the leading edges?Though I know not of what you speak, I know of another syndrome, it used to happen to me on motor bikes, I used to call it the 50 hour syndrome. Just when I was getting comfortable within the first 50 hours on the thing, that was when the bugger would throw me.. my own stupid complacency. I know you can't afford to be complacent and wouldn't be, but it is something to watch with your 'new' ferel.Cheers,Nicholas TomlinAlarmist - www.alarmist.com.au - we scare for you

[asra]

Not sure birdy, but could it have been low speed flapping and what you heard was your rotors bottoming out.As you completed your turn the rotor disc angle would have been lowerd to fly out of it, stopping the flap ??????????????Sam.Melbourne Vic.

[asra]

Not sure birdy, but could it have been low speed flapping and what you heard was your rotors bottoming out.As you completed your turn the rotor disc angle would have been lowerd to fly out of it, stopping the flap ??????????????Sam.Melbourne Vic.

[asra]

Not sure birdy, but could it have been low speed flapping and what you heard was your rotors bottoming out.As you completed your turn the rotor disc angle would have been lowerd to fly out of it, stopping the flap ??????????????Sam.Melbourne Vic.

[asra]

Not sure birdy, but could it have been low speed flapping and what you heard was your rotors bottoming out.As you completed your turn the rotor disc angle would have been lowerd to fly out of it, stopping the flap ??????????????Sam.Melbourne Vic.

[asra]

Hi Birdy, I have a little understanding of this but not enough to place here without further research however, if you don't mind, I have included the link of the other forum so we can all monitor the replies quickly. It is http://www.rotaryforum.com/forum/showthread.php?t=8427 Oh, it was a privilege meeting you by the way, and of course your family.Barry Ferguson - BrisbaneLets Torque Hirth Power here...logic will get you from A to B - imagination will take you anywhere

[asra]

Hi Birdy, I have a little understanding of this but not enough to place here without further research however, if you don't mind, I have included the link of the other forum so we can all monitor the replies quickly. It is http://www.rotaryforum.com/forum/showthread.php?t=8427 Oh, it was a privilege meeting you by the way, and of course your family.Barry Ferguson - BrisbaneLets Torque Hirth Power here...logic will get you from A to B - imagination will take you anywhere

[asra]

Hi Birdy, I have a little understanding of this but not enough to place here without further research however, if you don't mind, I have included the link of the other forum so we can all monitor the replies quickly. It is http://www.rotaryforum.com/forum/showthread.php?t=8427 Oh, it was a privilege meeting you by the way, and of course your family.Barry Ferguson - BrisbaneLets Torque Hirth Power here...logic will get you from A to B - imagination will take you anywhere

[asra]

Hi Birdy, I have a little understanding of this but not enough to place here without further research however, if you don't mind, I have included the link of the other forum so we can all monitor the replies quickly. It is http://www.rotaryforum.com/forum/showthread.php?t=8427 Oh, it was a privilege meeting you by the way, and of course your family.Barry Ferguson - BrisbaneLets Torque Hirth Power here...logic will get you from A to B - imagination will take you anywhere

[Adrian S]

Birdy,Sounds like Retreating blade stall, definately something we all need to avoid. At Biggendon our guest speaker spoke about it within the context of the old Bensen blades and pulling high G manuevours. One thing you may find useful is the warning device they fitted to the early heads so you got advance warning of its onset. The fitting of a light spring steel tab from the teetering stops allows feedback through the stick prior to the onset of the blade stall. I will ask Pete Barsden to post a photo of what I am talking about as I wont get to my gyro for a few weeks to take a photo of what I have on one of my gyro's. If you want any more info give me a call 0427094552 or A/hrs WST 08 95612979.Regards,Adrian

[Adrian S]

Birdy,Sounds like Retreating blade stall, definately something we all need to avoid. At Biggendon our guest speaker spoke about it within the context of the old Bensen blades and pulling high G manuevours. One thing you may find useful is the warning device they fitted to the early heads so you got advance warning of its onset. The fitting of a light spring steel tab from the teetering stops allows feedback through the stick prior to the onset of the blade stall. I will ask Pete Barsden to post a photo of what I am talking about as I wont get to my gyro for a few weeks to take a photo of what I have on one of my gyro's. If you want any more info give me a call 0427094552 or A/hrs WST 08 95612979.Regards,Adrian