After seeing the short article in Quiet Flyer this month on the Vought XF5U-1 "Flying Flapjack", my long-lived desire to create one of these for myself has been revived, and I'm looking for suggestions and technical help in the design phase of my project.
I am going to first make a simplified test bed version using fanfold foam, in semi-profile configuration. The final model will be fully dimensional and made from depron for the most part. I bought a very nice paper model of the flapjack from which I will be scaling up formers and the like, so that part I think is covered. The Version One testbed will be an indoor/light outdoor park flyer type. I am unfortunately restricted in budget, so I'm looking at brushed speed 300-400 type can motors, likely on direct drive, and powered by nicads or most likely hydride battery packs. I know it before you type it: outrunners and lipos would do this job much better and more efficiently, (and if I had some ham, I could make a ham sandwich.... if I had some bread too). I'm asking for your best suggestions using what I have available to me, and lipos and outrunners are not in the budget at this time. I'm going with a simple 3-channel radio setup, elevon control with HS-55's and motor ESC. At this point, if I can get a decent five minute flight with good performance, I'll call it a win, knowing an eventual upgrade to lipos will cut weight and increase power and duration. My plan for mounting the motors is to use model rocket body tubes for the motor booms, reinforced with a bit of glassing and some new carbon fiber rod from Midwest. So much of the character of this plane comes from the twin big 4-blade props, I'd really like to find the right motor/prop combo to make this semi-scale look happen, without pulling too much current for the battery/esc. I see in the hobby lobby catalog that flying styro makes 3 and 4-blade hubs and blades that might work... I don't have motocalc or other similar tools to calculate the loads in advance, any help here? I'm guessing twin speed 400's and a six-cell hydride pack, that's as far as I've got, and don't know if one ESC can handle the twin load... Size wise, I'm thinking about a 25-inch span, which sounds like it would have a high wing loading, but is deceptive for this plane's configuration. The full scale plane was designed to be VTOL/VSTOL, working at high-alpha and slow speed for takeoff and landing. Any hints, tips, advice gladly considered. If you have pics or URL's you want to share, I'd welcome the info. When I have something significant to show in the way of progress, I'll post a link to a thread on RCgroups.com Thanks for your time and help. Mark RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
