I came across ScanEagle video on EngineeringTV that showed ffew things that I din't know about it - each wing is attached to fuselage by one pin, motor mount is very flexible ( for vibration isolation) - there is a good shot of it towards the end of the video. Video has two parts and there is comerciall in the middle ( i.e. don't close the video when commerical starts ( ~ 2 min into the video...)

http://engineeringtv.com/blogs/etv/archive/2010/03/25/scaneagle-unm...

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Comment by Ryan Beall on March 25, 2010 at 6:08pm
I saw the first launch off of a navy vessel when I was on my freshman cruise for the Naval Academy! So lucky! Amazing gear. Capability is by far the cutting edge right now.
Comment by Jack Crossfire on March 25, 2010 at 10:15pm


Having enough money to make custom 2" wide ribbon cable is 1 of the perks of government grants. No tangled servo cables here.



It's probably extremely braindead simple like mounting the firewall on 3 shock absorbers but it's definitely a wow factor.

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Comment by Morli on March 26, 2010 at 2:50am
I didn't realize the shock absorber would make the mount so flexible!!! Did I read some were that it should be firm else big trouble ? :(( , I should try this, can someone share close up of the firewall w/o cowl ? and where to find the so called shock absorbers that can handle small gas engines?. thanks
Comment by Leno on March 26, 2010 at 12:08pm
This is an image of the older 24i engine on a ScanEagle. While the engine has been greatly improved, the mounts have stayed the same. 3 shock absorbers was pretty darn close.


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Comment by Morli on March 26, 2010 at 1:23pm
Thank you Leno, I get the idea. Is the black thing with belt drive a starter motor or on-board generator or two-in-one? Any more close ups of other side too? thanks once again
Comment by Leno on March 26, 2010 at 2:22pm
Maxon motor turned into an alternator. They've since replaced this with an in-line one. The aircraft is started with a hand-held spin starter.

Here's a picture of the other side.


It's this the older engine but, I always loved the simplicity of it. The newer engines have a lot more gear attached to improve it's usabilty in multiple environments.

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Comment by Morli on March 26, 2010 at 7:09pm
thank you very much Leno, appreciate the photos & effort.
this is what I learnt from above pictures.
the engine is 24 cc( 3W engine?) but I guess newer one might be larger 26 or more , with rear carb, spark plug cable secured with jubilee clip !!,
belt driven on board alternator( converted maxon motor, what voltage?), three layer of mount assembly with two layers on shock absorbers,
modified for clock wise rotation, so uses regular prop turned other way around with standard spinner( love this part)
the exhaust is basic with not attempt to muffle and is pointing down rather usual up!
forward mount is like a horse shoe.
there is a small circuit board( probably a charging circuit?) connecting the alternator with 6-7 pin connector( why that many pins?)
Engine is side mounted at 8o clock position , the second picture on the top has eng @ 5o clock position & different head( more like nitro), but the video demo( from eng TV) shows it at 8-9 cock position with special flexible air duck for cooling the eng head. Any historical reasons on these positions & changes? how is the air intake managed?
What else should I see or learn from this picture?
Btw engine and whole assembly looks dusty but looks as if never run in( ?!!)
Can you please tell us more? thank you .
Comment by Leno on March 27, 2010 at 9:03am
The newer engines are 28cc and both are from 3W. The flexible intake you see on the newer engine was put there to further minimize vibrations that were affecting the camera. The newer engines are also extremely well muffled. When the cowling goes on, it makes a duct as shown in this photo.


Admin
Comment by Morli on March 27, 2010 at 2:55pm
Thank you very much Leno for all the info & photos. You have given us great insight on how it is done by pros of the industry. cheers.

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