{"product_id":"est10031-f15-4-29mm-model-rocket","title":"Estes Rockets - F15-4 29mm Model Rocket Engines (2pk)","description":"Take your flights to the next level with the Estes F15-4 engine - a powerful mid-power engine designed for model rocket enthusiasts seeking longer thrust duration and higher lift capabilities. With 49.61 N-sec of total impulse and a max thrust of 25.26 Newtons, this engine is built to launch heavier rockets to stunning altitudes with confidence and control.\u003cbr\u003e\u003cbr\u003eThe F15-4 offers more than just raw power - it's engineered for dependable, sustained flight. The 4-second delay provides a balanced coast period after burnout, ideal for deploying parachutes or other recovery systems at peak altitude. Its long 3.45-second thrust duration gives your rocket a smooth, graceful ascent, minimizing stress on airframes while maximizing trajectory efficiency.\u003cbr\u003e\u003cbr\u003eThis engine is a popular choice for larger rockets in the Estes Pro Series II line and other compatible 29mm models. Its consistent performance makes it an excellent pick for hobbyists looking to upgrade from E-class engines while staying within the ease of single-use, black powder propulsion. Whether you're launching for sport, altitude records, or payload testing, the F15-4 delivers dependable performance every time.\u003cbr\u003e\u003cbr\u003eWith its powerful thrust profile, long burn, and mid-delay deployment, the Estes F15-4 is perfect for high-performance rockets weighing up to 21 ounces. Expand your launch capabilities and experience the next level of model rocketry excitement with this hard-working engine.\u003cbr\u003e\u003cbr\u003eE and F sized engines cannot be shipped to Alaska, Hawaii, Puerto Rico or Guam.\u003cbr\u003e\u003cp\u003e\u003c\/p\u003e\u003chr\u003e\u003cdetails open=\"\"\u003e\u003csummary\u003e\u003cb\u003eIncludes:\u003c\/b\u003e\u003c\/summary\u003e\u003cul\u003e\n\u003cli\u003e2 F15-4 Engines\u003c\/li\u003e\n\u003cli\u003e2 Starters\u003c\/li\u003e\n\u003cli\u003e4 Starter Plugs\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/details\u003e\u003cbr\u003e","brand":"Estes Rockets","offers":[{"title":"Default Title","offer_id":47959152885972,"sku":"EST10031","price":32.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0879\/6966\/files\/est10031.jpg?v=1779200212","url":"https:\/\/www.hobbyrecreationproducts.com\/products\/est10031-f15-4-29mm-model-rocket","provider":"Hobby Recreation Products","version":"1.0","type":"link"}