Avion
Active Member
Hello to everyone...
A question for Orion but everybody else input would be greatly appreciated...
I am a fan of a tandem wing aircraft. Currently i am doing a reserach on the Flying Flea, canard configuration and general tandem wing aircrafts. I've made a post on the Flea board re cg range (see below). Can you please comment if i am at the right track here. Thanks.
"Rob, thanks for all the info - here goes another tricky question
Yes, it does seem from all the research i've done that the Flea Cg range is less than a conventional a/c and therefore potentially more dangerous if set incorrectly. The one matter i am puzzled about is that the cg location is set at 25% (plus or minus degree or two) but the 25% cg is what you would find in a conventional a/c with a tail. So beside being a canard a/c as per Kirk Sutton's earlier posts (which has it's advantages re stalling) what is the purpose of the large rear wing. As per your posts the rear wing only flies with 10-20% of the load (or maybe even less). Could't you do the same with a normal a/c tail ( a flying tail) and make it much smaller and increase the gap so it would look almost like a conventional a/c and keep the 'living wing' and it's advantages! I do appreciate the fact of a a/c being a canard configuration with it's benefits, which you would loose in this case but to put that aside just for this example... what do you get?
In reality how much of the work is the rear wing really doing? My suspicion is that the purpose of the large rear wing in the Fleas case is the advantage of a parachutal descent and a stall proof behaviour (a la canard). Which, mind you are not and insignificant advantages. The disadvantage is the short cg range which can get you in a trouble.
On the other hand if you look at the Arsenall Dellane (Koen van der Kerchkove website has a lot of information) they say that the a/c had a fantastic cg range, a lot more than a conventional a/c. So could't you do something with a flea design, increse the gap (horizontaly) load the rear wing more and get the benefit of a good cg range?
Everybody's opinion would be greatly appreciated...
Regards
Thomas"
end of post..
A question for Orion but everybody else input would be greatly appreciated...
I am a fan of a tandem wing aircraft. Currently i am doing a reserach on the Flying Flea, canard configuration and general tandem wing aircrafts. I've made a post on the Flea board re cg range (see below). Can you please comment if i am at the right track here. Thanks.
"Rob, thanks for all the info - here goes another tricky question
Yes, it does seem from all the research i've done that the Flea Cg range is less than a conventional a/c and therefore potentially more dangerous if set incorrectly. The one matter i am puzzled about is that the cg location is set at 25% (plus or minus degree or two) but the 25% cg is what you would find in a conventional a/c with a tail. So beside being a canard a/c as per Kirk Sutton's earlier posts (which has it's advantages re stalling) what is the purpose of the large rear wing. As per your posts the rear wing only flies with 10-20% of the load (or maybe even less). Could't you do the same with a normal a/c tail ( a flying tail) and make it much smaller and increase the gap so it would look almost like a conventional a/c and keep the 'living wing' and it's advantages! I do appreciate the fact of a a/c being a canard configuration with it's benefits, which you would loose in this case but to put that aside just for this example... what do you get?
In reality how much of the work is the rear wing really doing? My suspicion is that the purpose of the large rear wing in the Fleas case is the advantage of a parachutal descent and a stall proof behaviour (a la canard). Which, mind you are not and insignificant advantages. The disadvantage is the short cg range which can get you in a trouble.
On the other hand if you look at the Arsenall Dellane (Koen van der Kerchkove website has a lot of information) they say that the a/c had a fantastic cg range, a lot more than a conventional a/c. So could't you do something with a flea design, increse the gap (horizontaly) load the rear wing more and get the benefit of a good cg range?
Everybody's opinion would be greatly appreciated...
Regards
Thomas"
end of post..