Wing Loading, again
05-11-2017, 06:44 PM
#1
Wing Loading, again
My god guys, I have this VQ P-40 (62 inch span) and the manual tells NOTHING about the Wing Area or Loading,
I know people put 20cc size gassers in this size War Plane,, I was told by the seller to put my Zenoah 20cc in it, well the Zenoah 20 weigh in at 41o.z. "less" Ignition Battery,
it's frustrating, and I feel like a child having to post and ask because half the people say "no,no, don't add weight" while the other half mount big heavy engines in these small .60 size planes,, one guy told me (quote) "62 inches is a lot of Wing Area",, what ??,, to me a 41o.z. engine plus Ignition Battery sounds like a lot of weight for a 62 inch Span wing shaped like a P-40's wing,
can I get comments
thanks guys
Jim
I know people put 20cc size gassers in this size War Plane,, I was told by the seller to put my Zenoah 20cc in it, well the Zenoah 20 weigh in at 41o.z. "less" Ignition Battery,
it's frustrating, and I feel like a child having to post and ask because half the people say "no,no, don't add weight" while the other half mount big heavy engines in these small .60 size planes,, one guy told me (quote) "62 inches is a lot of Wing Area",, what ??,, to me a 41o.z. engine plus Ignition Battery sounds like a lot of weight for a 62 inch Span wing shaped like a P-40's wing,
can I get comments
thanks guys
Jim
Last edited by the Wasp; 05-11-2017 at 06:51 PM.
05-12-2017, 12:02 AM
#5
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Much depends upon where the CG ends up. On most warbirds I would say don't worry about the weight up front as you will most likely need it there anyway. However, the P-40 is one of those that has a long enough nose that you may or may not need a bunch of weight up front in order to achieve the proper CG. I would do some preliminary testing to try and find out if the G20 will make the airplane extremely nose heavy or not. If not then the 20cc would be a fine choice for a 62" P-40. I have two 64" span Hellcats, one with a DLE 20 and one with an Evolution 20, and while they have plenty of power it is certainly not too much by any means. One is about 11 pounds and the other is about 11 3/4 pounds RTF. Both required nose weight so a lighter engine would have been a moot point. My .02 cents.
05-12-2017, 01:34 PM
#9
well crap, my head just exploded !!
Chad Veich, I hear you, but, I was just using my Zenoah as an example of weight, if I did use it I would have to cut a 2&1/2 inch hole on one side of the Cowl for the Carb, and a much-much larger hole on the other side for the muffler, besides, to do some "preliminary testing" I would have to drill holes in the Engine Wall that I may not even use,,
for something different I wanted to buy the HP 120 Inline Twin 2st, with mufflers it should come in around the same weight as my Zenoah 20, but it will cost $600 with mufflers to get it in the plane, I'm frustrated, I can't even find a set of reliable Rotating Electric Retracts for it under $400
but as they say,,,,, "That's the Hobby"
Jim
Chad Veich, I hear you, but, I was just using my Zenoah as an example of weight, if I did use it I would have to cut a 2&1/2 inch hole on one side of the Cowl for the Carb, and a much-much larger hole on the other side for the muffler, besides, to do some "preliminary testing" I would have to drill holes in the Engine Wall that I may not even use,,
for something different I wanted to buy the HP 120 Inline Twin 2st, with mufflers it should come in around the same weight as my Zenoah 20, but it will cost $600 with mufflers to get it in the plane, I'm frustrated, I can't even find a set of reliable Rotating Electric Retracts for it under $400
but as they say,,,,, "That's the Hobby"
Jim
05-12-2017, 02:21 PM
#10
My Feedback: (3)
Just put the cowl on with no engine and keep adding weights inside the cowl until it balances and then weigh the weights. Won't be exact but will get you a good enough idea as to whether or not the engine and mufflers you are thinking about are too heavy for the plane.
Wing loading does't matter as long as your engine is the right weight or lighter than is needed to achieve balance. Its going to be what its going to be unless your willing to start carving weight out of the back end of the plane.
Wing loading does't matter as long as your engine is the right weight or lighter than is needed to achieve balance. Its going to be what its going to be unless your willing to start carving weight out of the back end of the plane.
05-12-2017, 04:23 PM
#12
My Feedback: (3)
Sorry, but no dice. He has a plane, and unless he's willing to modify it, the total engine/muffler/nose weight that is needed to achieve the correct CG is fixed. As long as his engine/muffler combo does not exceed the weight needed to achieve the correct CG, the wing loading is fixed regardless of the engine chosen. Your welcome to worry about the wing loading but its a meaningless exercise (again, unless your willing to modify the existing airframe).
05-14-2017, 07:22 PM
#13
Compare your VQ P-40 with my TF P-40... My plane has a 64" span and 697 sq in of area and weighs about 10.5 lbs. It has a Valley View 20cc engine (32 oz total weight) and balances just right. It flys very well.
Your plane with 62" span will have about 660 sq in of area and with the heavy Zenoah engine will weigh much more than 8 lbs. You're main concern won't be wing loading so much as getting the CG correct (will probably need tail weight), although wing loading may be a factor, too. I would look for a lighter engine. Are you confident flying a heavy plane that lands fast? Having too much power is never a concern as long as you know what the throttle stick does.
Horizon Hobby sells E-Flight rotating retracts that work for your plane. I've got them in my Warhawk.
Your plane with 62" span will have about 660 sq in of area and with the heavy Zenoah engine will weigh much more than 8 lbs. You're main concern won't be wing loading so much as getting the CG correct (will probably need tail weight), although wing loading may be a factor, too. I would look for a lighter engine. Are you confident flying a heavy plane that lands fast? Having too much power is never a concern as long as you know what the throttle stick does.
Horizon Hobby sells E-Flight rotating retracts that work for your plane. I've got them in my Warhawk.
05-14-2017, 07:23 PM
#14
Compare your VQ P-40 with my TF P-40... My plane has a 64" span and 697 sq in of area and weighs about 10.5 lbs. It has a Valley View 20cc engine (32 oz total weight) and balances just right. It flys very well.
Your plane with 62" span will have about 660 sq in of area and with the heavy Zenoah engine will weigh much more than 8 lbs. You're main concern won't be wing loading so much as getting the CG correct (will probably need tail weight), although wing loading may be a factor, too. I would look for a lighter engine. Are you confident flying a heavy plane that lands fast? Having too much power is never a concern as long as you know what the throttle stick does.
Horizon Hobby sells E-Flight rotating retracts that work for your plane. I've got them in my Warhawk.
Your plane with 62" span will have about 660 sq in of area and with the heavy Zenoah engine will weigh much more than 8 lbs. You're main concern won't be wing loading so much as getting the CG correct (will probably need tail weight), although wing loading may be a factor, too. I would look for a lighter engine. Are you confident flying a heavy plane that lands fast? Having too much power is never a concern as long as you know what the throttle stick does.
Horizon Hobby sells E-Flight rotating retracts that work for your plane. I've got them in my Warhawk.
05-15-2017, 10:42 AM
#16
radfordc, thank you, I have seen the E-Flights and they seen good, I would like to buy a set, but there has been some complaints of them failing straight out of the box..
I wont use my Zenoah, it's just too big for the Cowl,, I pretty much guess I will buying a Saito 125, but I will wait another week or so and think on it.. I'm sure with the Saito I will need to add weight up front, I know I can move the Rx Battery forward, but maybe I can move the Throttle Servo forwarded too
Jim
I wont use my Zenoah, it's just too big for the Cowl,, I pretty much guess I will buying a Saito 125, but I will wait another week or so and think on it.. I'm sure with the Saito I will need to add weight up front, I know I can move the Rx Battery forward, but maybe I can move the Throttle Servo forwarded too
Jim
