"Arerodynamics of Gyroplanes"

Chopper Reid

Senior Member
Joined
Jun 25, 2004
Messages
1,326
Location
Pooncarie. Australia
Aircraft
Rosco built, Suby 2.2, pod
Total Flight Time
4600 gyro hours
Are any of you familair or know anything of this extensive 356 page study released by the UK CAA. Its a joint research between the University of Glasgow and the UK CAA. The good Professor "Houston" man behind the report.

I would be interested in those who know anything about Professor Houston and this 'extensive' report. If its already been discussed here then please forgive me for missing it.
 
Peter Lovegrove had some interesting thoughts about both report and Author.
 
Peter Lovegrove had some interesting thoughts about both report and Author.

Where can I find out more information about Peter Lovegrove??
 
You’re right, Brian, the link didn’t work for me either.

Go to the members list and find Chippydriver, Dr. Houston’s pseudonym. Then you can open all of his posts.
 
Paul buy it and review it yourself.


Peter has been building and around gyros for over 30years here in the UK. A former engineering officer in the BRA he built the Bensen I am flying, and that is over 30yrs old.

Chippydriver's experience with gyros perhaps not quite as extensive.
 
It surprises me that not a lot was discussed about the Houston study, after all, I believe it was mentioned that it took 500,000 punds to compile it plus wind tunneling, many years work etc and yet it provoked so little response about such an important issue.

Am I missing something here, I would appreciate comments on this .

BTW, I got the link working thank you although I have not downloaded the PDF file yet but will do so.
 
I just skimmed over it, but the thing that jumped out at me was that he is treating the Lift and Drag of the rotor as seperate forces instead of components of the the Rotor Thrust Vector. And shouldn't the drag component lessen at higher speeds?

I'm wondering how much experience he had with spindle heads or overhead sticks.
 
Peter seems to have been greatly affected personally by Ernie Brooks's fatal crash. He searched hard for a technical explanation for an event that was probably a porpoising or zero G accident of the type that was all too common in Bensen-clone gyros back then.

I flew my first 100-150 hours with a spindle head, liked it and experienced no weirdness such as Peter predicts. I liked the gimbal head less, in fact, when I first got one. The gimbal head made the stick feel like it was planted in a pail of oatmeal. The spindle head had what was to me an enjoyably light stick force. I didn't fly over 70 mph and didn't try aerobatics, though.

(BTW, the only reason I bought a gimbal head at all was that the spindle in the Bensen spindle head is a little suspect from the structural viewpoint. I had mine magnafluxed a couple times because it worried me (a few did break in flight, with obvious consequences). The spindle was made by cutting various journal diameters into bar stock on a lathe. This is a bit like cutting them into a broom handle; you expose "end grain" at those points where the diameter changes. Shafts like this are better made by forging, since that process makes the grain follow the shape of the piece. The gimbal head uses a dumb old AN bolt as its spindle, and is more wholesome in that regard.)

I never experienced a tendency toward exaggerated flare such as Peter describes. Tipping the spindle aft certainly increases thrust (both lift and drag, more or less in proportion to each other), but the angle between the rotor disk (tip-path plane) and the spindle actually DEcreases when you do this. Why? RRPM increases, which in turn reduces the blowback angle at any given airspeed.
 
Last edited:
Brian-> It surprises me that not a lot was discussed about the Houston study, after all, I believe it was mentioned that it took 500,000 punds to compile it plus wind tunneling, many years work etc and yet it provoked so little response about such an important issue.

Am I missing something here, I would appreciate comments on this .

Brian,

this report would surely be of great benefit to the gyro community and I have gone to quite some length to make good use of it. Unfortunately Dr. Houston has declined all requests for support regarding his report (see #4 of this thread)
http://www.rotaryforum.com/forum/showthread.php?t=25941
If a report is not backed up by anyone it's very hard to make any use of it. I have also tried to get the program that was used but have not been successful here either. In March I have started to develope a mathematical model for gyros which I would like to match against the results (both computational and experimental) of this report because then one would be able to discuss the results on a scientific basis but unless I find some more people to support the effort (see http://www.rotaryforum.com/forum/showthread.php?t=27391) it will take at least another half year before that model is available. I hope I'll make it...;-)
 
Last edited:
The translation of this text requires too much time for me (Google translator), but the ideas of Peter Lovegrove are false. As Mike said, it is wrong to separate lift and drag. His sketches are misleading. Ratio lift/drag is without interest in this stories.
Jean Claude
 
Stick force depends upon cyclic flapping angle.

Rotor lift/drag ratio has nothing to do with it.

If the TV weather babe said; “The component of wind out of the East is 7.07 mph while the component of wind out of the North is also 7.07 mph,” instead of a “NE wind of 10 mph,” most people would at least flip channels.
 
JC -> As Mike said, it is wrong to separate lift and drag.

It is sound and well proven engineering practice to resolve vector quantities into components in a cartesian coordinate system. If the forumlae for the components are correct the resultant will also be correct and may simply be calculated by good old Pythagoras (but in fact that formula was known hundreds of years before Mr. P stepped in, as far as I know)
 
Last edited:
Juergen, Observe the sketch 5. You understand that Mike and I want to say: It is wrong to separate lift and drag, as long as to lose one of them.
 
Top