Flying Wing Crossbow Launcher

by MyGeekShow | March 15, 2014 | (9) Posted in Projects

After having some difficulty launching the heavier Raptor140B+ (carries three 5Ah batteries) I decided to invest the time into building a cross bow launcher.

It has a few key features that make it an excellent launch platform:
-Totally retains the airplane in all directions (gust of wind won't knock it off the the launcher)
-Trigger mechanism to quickly release the airplane
-Provides distance between the prop and the pilot
-Quick to use (takes only a few minutes to set up)
-Small space (small launcher and some cable)
-Easy to use (set it up, aim it, pull the trigger)
-100% repeatable

Tested it on the Raptor140A (now a glider) and it worked perfectly! After a dozen tests, I put the Raptor140B on it... Victory! The exit speed of the Raptor140B was 90kph/56mph, a perfect speed for climbing.

This will add a lot of safety and repeatability for launching these heavier flying wings.

See you next week!


Safety note: I maintained line of sight during this flight, and had my controller close by to take manual control as needed. The altitude read over 120m, but elevation increased during flight. True AGL for the flight is 100-120m. I avoided all airports and populated areas.

Raptor 140b+ Stats:
Weight: 2280g
Max Flight Time: 70min
Max Range: 97km
Stall Speed: 35kph
Cruise Speed: 90kph
Max Speed: 135kph
Radio Range: 1.5km
Energy Carried: 167wh (15,000mAh at 11.1v)
Drive Power: 850w
Total Flight Time on Craft: 7.0 hours
Total Flight Distance on Craft: 498km

The equipment used---
Raptor 140 airplane:

Radio Tx: ParkeFlyer Turnigy 9x Tx:
Telemtry: 915mhz 100mW 3DR
Laptop: Compaq Presario CG57
GPS Dongle:

Flight Controller: APM2.6
Reciever: 6ch FlySky
Telemtry: 915mhz 100mW 3DR
Battery: (3) 5.0Ah 20C Lipo:
ESC: 60A Brushless
Motor: 3542 1450kv brushless
Prop: 10x7 Carbon Fiber Folding
Servos: 11g digital
Onboard camera:

Learn More:
Raptor Details:
USA Trip Details:

Follow the Show:
Skype: MyGeekShow

Filmed, Edited, Produced and Published by Trent in Arkansas, USA


pintokitkat on March 15, 2014
It might be worth rebuilding the video without the embarrassing typo on the title.

Despite that, I love your confidence in using your car as the anchor. Image the insurance claim 'Well, I was firing a 5 pound drone at the car with a crossbow and it just, sort of smashed the door in.'
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MyGeekShow on March 15, 2014
What tpyo? ; )

Yeah, I've thought about that phone call... that would be interesting! Luckily, the location of the launch hook relative to the CG on the airplane essentially makes that an impossibility. Its been launched that way many times without even a close call. As you saw the glider was launched without my hands even on the controller, it naturally pulls up like a high start. Here is hoping it stays that way! Thank you for watching!
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UndCon on March 15, 2014
I think you should add some sort of support to the ground as it looks like u cannot hold the wing up on 1 arm. Mount it on a tripod or similar...
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MyGeekShow on March 15, 2014
Yeah it is heavy, too heavy for one hand. It launches just fine as it is, although it would be better with some kind of stand. Luckily, the USA trip will allow me to have an assistant!
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alibopo on March 16, 2014
Trebuchet launcher next please.... :) Great work on the x-bow mechanism though!
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MyGeekShow on March 23, 2014
Ha ha! That would be awesome!
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Widkin on March 23, 2014
Great idea and good video. Not sure I would call it a cross bow launcher, though. I imagined you launching it from a real cross bow, i.e. shooting it from an actual bow. But I guess that would be a bit too violent. Your idea seems great, although I agree that it is very brave to have the bungee attach to your car. :)

Good job!
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MyGeekShow on March 23, 2014
Yeah, for a plane that large you'd have quite the launch! But, it would be fun to try! : )

I'm brave, and I have insurance... wait, does it cover UAV launches? : )
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Flying Wing Crossbow Launcher