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Mister E engine size?

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Old 05-17-2012, 11:35 AM
  #1
flybyjohn
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Default Mister E engine size?

I saw this airplane in may 2011 Model Aviation Mag. and was wondering if it would be a good canidate for my magnum .15 engine. The specs are as follows.

wing span - 39.5"
wing area - 290 square inches
length - 32"
weight - 31 oz.
sugested motor - 480 outrunner eflight
suggested bat. 2100 - 2500 mah pack
rec. prop. apc 11x6

all balsa construction

I know the prop is way bigger than I would use but do you think the airframe is the right size for a .15 engine?

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Old 05-18-2012, 04:32 AM
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Default RE: Mister E engine size?

Here's a picture if anyone needs a visual image.

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Old 05-19-2012, 06:03 AM
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Default RE: Mister E engine size?

My Gee Bee "Y" project has really close specs to yours.

The original electric specs are:
wing span 40"
Wing area 306 square inches
length 30"
weight 32 oz

I installed a OS .25 la w/ pitts style muffler and the weight is now 47 oz which gives me a wing loading around 22 oz/sq foot

It's ready to maiden but the wind has not been cooperating. I now have 2 new planes to maiden (other one is electric Polaris with LEDs for night flying). Hopefully the wind will settle down today or tomorrow. When I get the maiden done will let you know how it performed.
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Old 05-19-2012, 04:16 PM
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Default RE: Mister E engine size?

@flybyjohn
From what I can tell I belive the aircraft would be a good choice for that sized engine. I've flown many E-flite 480 motor aircraft and putting a .15 glow powered engine in there should do the trick. Just be sure to keep your weight close to what the aircraft was built for. Just be aware that you'll probably need to fly the aircraft more like the "real thing". I say this because often times rc pilots will over power their airplanes (a power to weight ratio of higher then 1:1) and when they get into trouble (e.g., stall close to the ground) they can throttle it up, blast off, and break free. When you are flying with a weight ratio that is not 1:1 but more like the real deal - you'll just need to be aware that your plane will handle differently.Ok, I'm off my aviation lesson soap-box.

I like your choice of aircraft!


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Old 05-21-2012, 05:07 AM
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flybyjohn
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Default RE: Mister E engine size?

Thanks for the comments guys. I have been going back and forth between this plane and the Herr lil something extra. Mister E looks like a pretty quick build with a few mods for the fuel tank and a beefier firewall. If I build it, I will have to call it Mister G (glow).
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Old 05-22-2012, 05:25 AM
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@flybyjohn
I'd like to make a few corrections to my statement above.

Regardless of the power plant you use, the aircraft will technically fly the same. However, when you have a power to weight ratio higher then 1:1, you will be able to do things more quickly (e.g., rapid take offs and flips) and also perform maneuvers the aircraft may not have been intended to do (e.g., hovering a piper cub). When you're closer or below the 1:1 ratio the most dangerous element in r/c is stalling. Not because you can't stall at high speeds (see below) but because the pilot is attempting to maneuver the aircraft without sufficient lift. I've seen many-a-rc-pilot throttle down the runway and pull up too quickly on take off, stall, roll a wing over, and crash. All because they are use to flying with extra power(Note: The aircraft in the video did not "tip stall". It stalled asymmetrically (one wing dropped before the other) and the corrective actions by the pilot aggravated the stall which is why it violently flipped the other direction).

Me? I appreciate flying an aircraft the way it was meant to be flown. That's probably why you'll never see me hovering a Piper Cub.


High Speed Stalls
A wing can stall at any speed above the ‘slow stall speed’ for the same reason. For example, an aircraft may go into a steep dive. At the bottom of the dive the pilot may pull back on the stick to make the aircraft flatten out and then climb. If done too quickly, or because of poor aircraft design, the wings can be pointing up but momentum i.e. gravity, continues to make the aircraft go down. If the wings are pointing up but the direction of travel is down the critical angle is exceeded and a high speed stall occurs.
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Old 05-23-2012, 04:48 AM
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Thanks for all the info apwachh0lz. I never muscle anything off the runway for just the reasons you stated. I let all my airplanes start flying before they lift off the runway if you know what I mean. I have a variaty of airplanes, some with a great power to weight ratio and some with a low ratio. I will muscle around some of the planes in the air (using that great thrust) but I found on take off, even with the high thrust to weight ratios, it is best to just get some speed up and the plane will just lift off the runway when it is ready.

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Old 05-24-2012, 07:01 AM
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"...it is best to just get some speed up and the plane will just lift off the runway when it is ready." - flybyjohn

I like your style
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Old 12-06-2013, 12:34 PM
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I like your choice of planes, I just ordered the kit from Creative Hobbies. I plan to go electric tho, I am pretty much a novice so I am not sure what engine to use or ESC or servos. The plans are kind of schetchy..

Rocketman

I was curious if you know where I can get a reprint of information for more details.
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