Film is a series of 14 flights detailing the 4th trim session for the rubber-powered free-flight model of the 31" 1914 Martinsyde S.1. The model has a smaller prop & a new pair of wings, swapping out undercambered wings for ones with sliced ribs and flat bottoms. The 31" model was built by Tom Hallman. Filmed at Barron Field in Wawayanda, NY, May 14, 2021. Music via motionarray.com. Model based on this plan: http://2002.hallmanstudio.com/Martins... Article on the use of dethermalizers: http://2002.hallmanstudio.com/DT.pdf Badge Classic DT & spring (at the bottom of the page): http://www.starlink-flitetech.com/tim... Here are some photos of the simple, adjustable thrust plate used on the Martinsyde & Seafire. http://2002.hallmanstudio.com/thrustp... http://2002.hallmanstudio.com/thrustp... Geneseo FAC Nats Journals from 2016 & 2018: http://www.maxfliart.com For more info on free-flight rubber-powered models, check these websites: https://brooklyn-balsa.square.site http://www.easybuiltmodels.com/ https://volare-products.myshopify.com http://www.flyingacesclub.com National Free Flight Society - https://freeflight.org/ Mike Stuart's Flying Scale Models - http://www.ffscale.co.uk/ https://www.freeflightsupplies.co.uk Flying Aces Club merchandise: https://www.cafepress.com/shop/Flying... All profits support Flying Aces Club activities. Center of Gravity merchandise: https://www.cafepress.com/shop/Center...