Foamboard Scratchbuilding Challenge: Largest Wingspan

ExAir

Junior Member
Here is a challenge to take foamboard scratchbuilding techniques to the maximum: HUGE WINGSPAN!


I've created a contest for building the largest wingspan scratchbuilt foamboard RC airplane using the Armin Wing airfoil technique and capable of controlled electric-powered flight for 60 seconds, surviving a landing, and immediately flying again. Wingspan shall be measured in straight-line distance between the cambered component of the wingtips of an unsupported wing on the ground, rounded down to nearest full inch.

See the FliteTest article on the "Armin Wing" airfoil technique.
http://flitetest.com/articles/Easy_Foamboard_Airfoil_the_Armin_Wing

The prize for the largest wingspan airplane meeting these requirements is a $75 store credit coupon from TapeBrothers.com. And some serious bragging rights!

This contest is open to builders and pilots WORLDWIDE. Please note TapeBrothers.com is located in Florida, USA so shipping costs will vary depending on location. The prize is still $75 for any winner.

Multiple entries are allowed. If you submit an entry, then increase your wingspan, then you may resubmit before the deadline. The deadline is midnight Sunday 12 August 2012.

RULES:

Aircraft:
Wing - must incorporate an Armin Wing airfoil technique where foamboard is folded to make lower surface, leading edge radius, and upper surface with one continuous piece of foamboard. Due to the size of commonly available foamboard (ie: Readi-Board, Dollar Tree foamboard) the maximum practical chord is 15". Therefore the maximum allowed total chord including control surface is 15". Folded extruded polystyrene (ie: Depron) is allowed. Any variation of formers, spars, and control surfaces is allowed. Suspension lines and struts are not allowed.
Airframe - predominantly foamboard, electric propulsion, radio controlled. All other design parameters are up to the builder

Flight:
Video-proven powered takeoff, 60 second flight, controlled landing at same elevation, and repeat takeoff with resumed controlled flight.

Measurement:
Measure the wingspan on video so we can clearly see the dimension from cambered wingtip to wingtip. No non-cambered-airfoil protrusions may be counted. In the event of a tie, the winner will be determined by Experimental Airlines on subjective criteria including creativeness of design, quality of build, style and finish.

Duration:
4 weeks from time of contest announcement are allowed to build, test, fly, document, and post the video as a video response to this video. Video responses that meet the contest requirements will be posted immediately as they are received. The winner will be announced within 2 weeks after the deadline and the TapeBrothers.com $75 store credit coupon will be transmitted to the winner.

Why Armin Wing? I hope to stimulate innovation and creativity that can be adopted by other builders using this technique. I'd really like to see how far we can take this design.

Why two takeoffs and a 60 second powered flight? One could make an enormous plane that flew only once and couldn't survive a landing, but the building techniques wouldn't translate as well to a practical airplane with reproducible flight results. Reusability is key.

Why 15" chord? This is the practical limit for commonly available foamboard using the Armin Wing airfoil. Realistically it's more like 13" once the camber is accounted for. Certainly foamboard planes could be made with wingspans up to probably 50' using multiple foamboard panels, but since we are specifically exploring the Armin Wing and keeping the dimensions within the means of hobby-level builders we will honor the natural dimensions of the foamboard and the airfoil technique.

Why measure in full inches? This is to reduce measuring error and eliminate conflict between builders using different units and degrees of precision (1/4" vs .2 inches vs. 755 thousands, etc.). We just need to use the same exact unit to be fair. Outside US? Sorry, I like metric too, but please measure in inches for consistency.

Why allow Depron? I want to be sure builders outside North America are able to join the project and enter the contest even if they can't get Readi-Board. Depron has no more advantages than disadvantages compared to papered foamboard. The airfoil bending technique is essentially same, so anything we learn from one can be translated to using the other.
 

SteveOBHave

Senior Member
Excellent comp - I'd love to have a shot but unfortunately here in Aus - the pieces of foamboard here are around $15 a sheet so it starts getting spendy pretty quickly. I am looking forward to seeing what people come up with though :D

Kudos for all the effort you put into the hobby and the work you do to promote it. For me anyway, your work and ideas have led to some really great experimental experiences and successes.

Steve