Drag polar reading material suggestions?

[ChiefPilot]

I'm wondering if anyone here might be able to point me in the right direction for reading material either in book form or on the web. Specifically, I'm interested in learning about the relationship between AOA, airspeed, and weight for a given aircraft and the resulting total drag. Clearly, for a given aircraft at a certain weight and airspeed, there will be a certain angle of attack. As either airspeed or weight/g-loading vary, AOA varies thus altering total drag. I'm interested in learning more about how this is determined. Ultimately, I'd like to be able to develop a set of drag polars for my -6A and then compare them against actual data from my phase 1 flight test data. Not knowing much about the topic, I'm not sure this is feasible, but I'd at least like to learn more about it.

"Aerodynamics for Naval Aviators" touches on this topic but doesn't go into any detail about how a drag polar is produced, so I'm looking for any further reading suggestions.

Thanks!

[hevansrv7a]

You are fortunate that you are interested in the 6A. Start with the CAFE report. Then you may want to look at my triangle tool that has been filled in with data on the 6A from CAFE. You may want to try using Van's published numbers on the same spreadsheet. Just go to my web links (signature) to find all this stuff.

Unfortunately, you will not find much there about angle of attack as such, but what you will find there will give you the drag polar very nicely. You may also want to review my presentation from 2010 at Air Venture which describes methods by which you can test your own airplane.

I am always willing to discuss that presentation and this year's by any mode of communication you find convenient.

If the engine is older and/or has enough fore-aft movement in the crankshaft, you can build and install a zero thrust device just like CAFE did. It's the design Jack Norris used on a C-152 and his Luscombe. It's proven to be an accurate way to do this kind of research. That is the best possible way to test the aircraft. If that is not possible, the methods that I described last year are a pretty good alternative and have been verified to some degree in a C-152 against Jack's data.

Jack's two EAA articles from 1995 are also on my info page.

Good luck and have fun!

[ChiefPilot]

Wow, thanks - that's just the kind of information I was looking for! I hadn't read the CAFE report on the -6A either - very interesting stuff!

Thanks!