View Full Version : Variable Geometry Wings

Rusty Cessna
6th Jan 2002, 05:08
Does anyone know where I would be able to find some technical reading on Variable Geometry wings?


7th Jan 2002, 21:41
Try "Aerodynamics for Naval Aviators." If you have any questions about the practical aspects of flying a VG wing, drop me an email.

[ 07 January 2002: Message edited by: Roadtrip ]</p>

Rusty Cessna
7th Jan 2002, 23:15
Cheers Roadtrip, know where I can get a copy?


9th Jan 2002, 00:00
RC - I don't know of a source in the UK. It's a unclassified US Navy textbook commonly available. Here's one source in the US. As I recall there's not a whole lot about VG in it but it is pretty technical. Certainly A LOT more information and detail than any pilot has the right not know.

<a href="http://www.buildersbooks.com/aerodynamics_for_naval_aviators.htm" target="_blank">http://www.buildersbooks.com/aerodynamics_for_naval_aviators.htm</a>

Another good book is "Modern Combat Aircraft Design." You can do a web search and find it.

I'm sure there must be a bunch of UK written texts on aerodynamics/VG that would be more readily available where you are.

Try going over to the military thread and see if you can dig up any F-1 TORNADO pilots. They may be able to steer you towards some RAF texts or Flight Characteristics Sections from flight manuals. As as alternative, try some universities that have Aero Engineering libraries.

Good luck.

9th Jan 2002, 00:29

Aeordynamics for Naval Aviators is distributed in the UK by Star publications. I don't know their address but it has been discussed in pprune quite recently. It is an excellent book covering most aspects of aerodynamics in considerable detail, but probably costs 40 or 50 pounds.

You have not said why or to what level you wish to study this subject. If you need fairly basic stuff I can probably send you some. If however you want to know the full nine yards (including all the complex mathematics) then you will need to buy some books.

[ 08 January 2002: Message edited by: Keith Williams. ]</p>

Rusty Cessna
9th Jan 2002, 01:08
Thanks for all the help!

Basically I'm looking to do some background research to a) understand the subject, an b) see if it is suitable for my A level physics investigation.

Thanks again,

Genghis the Engineer
9th Jan 2002, 01:52
Hunting around a good aeronautical library Rusty, you should find a lot of information. If you are anywhere near London, ring the RAeS and see if they'll let you spend a few hours in their library if you've nothing more convenient. Apart from normal aircraft design books (and check out Darrol Stinton's "Design of the Aeroplane", and Kermode's "Flight without Formulae" particularly) and aerodynamics books, look up some books on Tornado and MiG23.

If you want a Janet and John introduction...

Swing wings were originally a Barnes Wallis idea, who spent a lot of time experimenting with them on models but never built a full scale swing-wing aircraft. The advantage of them is at high speeds they allow a structurally and aerodynamically efficient high speed shape whilst at low speed they can give good low speed handling and lift. Ideal for an aircraft like the Tornado GR1 which wants to be able to muck about just below M=1 down valleys, whilst still operate from finite length runways.

The biggest headaches are mechanical - the hingepoint is a fragile element, the stores have to be kept in-line with the fuselage, the actuators are very heavy and a single actuator failure can mess up the whole system. Landing a Tornado with the wings stuck swept is difficult and can in some conditions mandate ejection.

Overall, I'd suggest that the aerodynamics of a variable sweep wing are reasonably straightforward, and the engineering extremely complex. If this is what you want, I'd suggest it is an ideal subject for an A-level Physics project.

However, if you feel that you could do with more aerodynamics and more engineering, I'd suggest looking either at Delta wings, or basic aircraft stability - both of which will give you ample opportunities to do mark-grabbing experiments, whilst simulating transonic flow in a school physics lab might be fiddly. Deltas are also where it's at at the moment, I don't think anybody looks likely to develop another swing-wing for a while, but Deltas are all the rage.


Rusty Cessna
9th Jan 2002, 02:21

That's excellent, thanks for the intro. I'm not anywhere near london so will have to try and source info from other places. I am pleased to say the actual investigation is purely a theoretical one, a research project, I've already done the practical!

Thanks again to everyone.

9th Jan 2002, 06:36
Genghis - We've had to land the B-1 a couple of times with the wing swept full back (67.5 deg). It's not pretty but can be done. Approach speed, lightweight, is 250k (which is also the tire limit). Of course, the tires go, and the brakes catch fire, but usually very little damage. Pretty exciting though, they say.

BTW, the engineers told us pilots early in the program, that, due to the redundant design, it was impossible for the wings to get stuck back. Yea, right, we said --You don't know how many clever and devious ways pilots have to break airplanes. How many times have you heard that one from a design engineer? Cheers.

D Beaver
9th Jan 2002, 08:57

Try <a href="http://www.abebooks.com." target="_blank">www.abebooks.com.</a> 19 used copies of "Aerodynamics for Naval Aviators" are listed for sale.

9th Jan 2002, 09:45
While not specifically relevant to this topic, I can certainly confirm the value of "Aerodynamics for Naval Aviators" and Kermode's "Flight without Formulae". I'd only ever managed to just scrape thru the various Principles of Flight exams until I began training for my instructor rating.

At the instigation of my intructor, the late and great George Campbell of Mudgee, NSW, Oz, I got hold of both books. Not only did they explain everything I'd ever need to know about Principles of Flight, they also - naturally enough - served as the basis for all my briefings.

The thing I found, especially in Kermode's book, was that the deeper I got into the subject, the deeper I wanted to go ... all the time drowning just a little bit more. The subject is very much like that, for those who are as interested in it as I was.

I still have both books and all my original briefings but, because I've moved around a bit in the last few years, they've been in storage. I've often missed not having them with me.

Genghis the Engineer
9th Jan 2002, 14:52
I agree with Roadtrip about the need for failure resistant design.

"The difference between a machine that can go wrong, and one that can't, is that when the machine that can't go wrong goes wrong, it is almost impossible to fix".

I'm sorry to say that I had nothing to do with the B1 which much have been a fascinating project. However, my limited experiences of the dreadful Tornadoesntgo F2/3 never greatly inspired me.

Rusty, you are probably at a point in life where expenditure on student membership of the RAeS would be worthwhile. To members, the library catalogue is online and they'll post books on loaan to you in return for a cheque for their postage and packaging when you send it back. I have made use of this facility on numerous occasions. (www.aerosociety.com)


[ 09 January 2002: Message edited by: Genghis the Engineer ]</p>