# Rotor solidity.

#### Arco

##### Junior Member

Then further questions raised their ugly heads, the rotor disc loading, is this calculated to include or exclude the rotor bar swept area, and same question for the blade loadings, so, I played with an excel spreadsheet out of curiosity to see what magnitude of difference with and without the hub bar made.

You have to consider the hub bar included all the time, like part of the blade.
The radius is the sum of the blade length plus half of the hub bar length. It is the distance from the center of rotation shaft to the tip of the blade, with the disc flat, no conicity is taken in account.

#### Mac

##### Member
I have been listening to Chuck Beaty and Doug Riley since "Norm's Forum"

Chuck Beaty: dry humor, sometimes answers a question with a question/thought invoking, inspires you to think and always leads you to the answer.
Doug Riley: has the knowledge and experience to convey the science to you as if you are both at your dining room table talking about gyros.

The two of them bring vast knowledge and experience to the forum.

If only we could get their knowledge and experience compiled into a book !!!!

#### All_In

##### Gold Supporter
PRA would pay to have a book published for both Chuch and Doug!!! As you are so correct, and none of us are getting any younger.

#### Doug Riley

##### Platinum Member
I got most of what I know about gyros from Chuck. As a VERY young gyronaut, I read his Sunstate newsletters like Moses' two tablets. I then pestered him with questions, and he graciously answered them in neat, longhand letters (no email back then). At age 18, I didn't even think to send him a few stamps for his trouble.

A surprising amount of the information we need is in Gessow and Myers' Aerodynamics of the Helicopter, a college-level textbook. It was written in the early postwar period, when helicopters were just coming into their own. Autogiros were still a recent memory. In this book, you often can skip the differential equations, look at the pictures and still get a sense of things.

The old NACA reports on various tests of gyros in the 1930's are instructive, too. They are now online. Some of their approaches to rotor theory and design turned out to be sorta dead ends, but even those are educational. (E.g. they talk about making rotor blades tail-heavy on purpose in order to produce a sort of constant-RRPM effect, apparently before trailing-edge reflex became common. Kids, don't try this at home!)

Finally, some basic mechanics-of-solid-bodies (as taught in high school physics classes) doesn't hurt. The relationships among mass, weight, force, work, energy, speed, velocity and acceleration as physicists regard these things must be understood if you are fooling around with flying machines.

#### Martin W.

##### Active Member
I have been listening to Chuck Beaty and Doug Riley since "Norm's Forum"

Chuck Beaty: dry humor, sometimes answers a question with a question/thought invoking, inspires you to think and always leads you to the answer.
Doug Riley: has the knowledge and experience to convey the science to you as if you are both at your dining room table talking about gyros.

The two of them bring vast knowledge and experience to the forum.

If only we could get their knowledge and experience compiled into a book !!!!
PRA would pay to have a book published for both Chuck and Doug!!! As you are so correct, and none of us are getting any younger.
It would be a tremendous amount of work .... sorting ... categorizing ... and editing ... but all the information is already here on this forum for a book.

Go through all the posts by Doug and Chuck and other qualified members and glean the best of the best and compile it in book form

Could be done as a series of questions and answers ... questions we have all had through the years ... and practical answers we can all relate to.

That way no "story line" is required .... mostly just a compilation . Builders and students would treat it like scripture

Find someone who has gyro knowledge and some journalism skills who could devote the time required.

#### XXavier

##### Member
There's a free book in the internet on autogyro design. It's for model gyros, but it's a good book...

#### All_In

##### Gold Supporter
Doug & Chuck
What I was thinking was more of a biographical book. Telling it from the beginning as Doug just recanted how and who he learned from.
Then add your experiences, lesson learned, like flying with and without an HS to teach aerodynamics the way you do when you tell us what you learned and then explain it to us in your posts. Chuck could do the same with his models and what he learned at each year of his life with flying adventures mixed in. How about the water landing, its a great story and teaching at the same time...

Last edited:

#### All_In

##### Gold Supporter
There's a free book in the internet on autogyro design. It's for model gyros, but it's a good book...

Thank you!!

#### JETLAG03

##### Active Member
Possibly rather than a book that tells a story but a reference book. Subjects, such as for example Rotors with sub sections for design, construction, calculations etc etc.
Each section with the questions regarding that subject with answers and more importantly explanations as to how and why and where appropriate supporting calculations and index to the calculations and their elements as frequently posted by @Jean Claude.
I personally prefer to see the supporting data for a reply, not because I do not believe the post, but, because by working through the calculations I often find a deeper understanding of the subject.
Even an extremely complex subject can be within the grasp of many if the poster/tutor/trainer has the ability to break down the subject into small sections carefully explaining each step, this is the mark of an excellent communicator.

quote" The single biggest problem in communication is the illusion that it has taken place – George Bernard Shaw. "

Excellent as they are, forums are a limited form of sharing, teaching and learning and is restricted by virtue of the divergence of any post. A forum and it's posts are sometimes like a dozen guys at a bar having a few beers and chatting, the subject matter changes constantly, brought back and then changed again.

A near real life reflection of friends interacting, with all the misunderstandings, disagreements and various points of view that one would find in a bar, but sadly without the beer.

The pub, by the way, is the one thing I miss living in France, pubs/bars do exist here, but, they are a pale imitation of the real thing (sorry Jean mi, you know it is true)

phil (de fer)

#### XXavier

##### Member
The market is very small. We gyro pilots are few and scattered... That's why reference books on the subject simply don't exist (with the exception of the German one, that hasn't been translated...).

#### Resasi

##### Gold Supporter
What I used to do was collect particularly informative posts, explanations, spread sheets, formulae etc. These were also collected in the ‘Gyropedia’ ? I think it was called (but not the present one now run by Phil Harwood), which was accessible to all but that then disappeared.

It may well have been set up by someone and then simply closed to public access, for some reason Tim O'conner springs to mind but I may be completely wrong on that.

I had not one or two but three hard disc failures all on Toshiba computers, and I both lazy and ignorant had not backed up adequately. I did however stop using Toshibas and absconded to Apple.

#### All_In

##### Gold Supporter
...

It may well have been set up by someone and then simply closed to public access, for some reason Tim O'conner springs to mind but I may be completely wrong on that.
Yes, Tim used to maintain over 10K documents, IIRC on Wikipedia. Tim has moved on to motorcycles as his main passion today.
My plan is to put them on PRA's new website Library search page. If Tim still has them and will provide them to us.

#### Resasi

##### Gold Supporter
That would be great John, there was a lot of very useful information in that collection.

Replies
8
Views
1K
Replies
33
Views
3K
Replies
2
Views
592
Replies
76
Views
8K
Replies
5
Views
3K