OldSchoolFlyer
I did some air speed measurements using My FrSky Taranis with the ASS-70 air speed module. The jets all had the same 2826 Turnigy motor 2200/35C 3 cell battery, skywalker 40 amp ESC and the same 6X4.5 prop. The wings are similar except the F-18 which has the KD airfoil and front spoiler. See photos. I modified the F-22 using the F-35 tail. The F-18 only mod is the front spoiled on the KD airfoil. The F-15 is 100% stock. The Mig-29 has extra sweep back in the wing. See close-up of pitot tube on side of F-22 IMG_20180517_101917.jpg  IMG_20180517_101840.jpg  Speeds: F-22 48.0 mph F-15 59.1 mph Mig-29 56.3 mph and the F-18 66.7 mph No surprise the F-18 is FAST but surprised the F-22 at 48.0 was the slowest. I am going the make some additional test to try and determine why some are faster. I am also going to make some weight measurements but these number don't really indicate weight is the issue, since the F-22 is the lightest. YOUR THOUGHTS ?????[A[/ATTACH] IMG_20180517_101917.jpg  IMG_20180517_101840.jpg  IMG_20180517_101824.jpg  IMG_20180517_101804.jpg  IMG_20180517_101807.jpg  The F-15, F-18, Mig-29 have ailerons and elevator. The-F-22 has only elevens.
Old School Flyer
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Wildthing
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I did some air speed measurements using My FrSky Taranis with the ASS-70 air speed module. The jets all had the same 2826 Turnigy motor 2200/35C 3 cell battery, skywalker 40 amp ESC and the same 6X4.5 prop. The wings are similar except the F-18 which has the KD airfoil and front spoiler. See photos. I modified the F-22 using the F-35 tail. The F-18 only mod is the front spoiled on the KD airfoil. The F-15 is 100% stock. The Mig-29 has extra sweep back in the wing. See close-up of pitot tube on side of F-22 [ATTACH] [ATTACH=full]55095[/ATTACH] [ATTACH=full]55096[/ATTACH] Speeds: F-22 48.0 mph F-15 59.1 mph Mig-29 56.3 mph and the F-18 66.7 mph No surprise the F-18 is FAST but surprised the F-22 at 48.0 was the slowest. I am going the make some additional test to try and determine why some are faster. I am also going to make some weight measurements but these number don't really indicate weight is the issue, since the F-22 is the lightest. YOUR THOUGHTS ?????[A[/ATTACH] [ATTACH=full]55095[/ATTACH] [ATTACH=full]55096[/ATTACH] [ATTACH=full]55097[/ATTACH] [ATTACH=full]55098[/ATTACH] [ATTACH=full]55099[/ATTACH] The F-15, F-18, Mig-29 have ailerons and elevator. The-F-22 has only elevens.

Possible the motor is getting lazy, esc timing, throttle range setting, battery that is if it was a different one used in each.
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OldSchoolFlyer
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Possible the motor is getting lazy, esc timing, throttle range setting, battery that is if it was a different one used in each.

Lots of variables ESC Motor age and settings. I wil try to narrow the variables and continue to compare the speeds. Thanks
Old School Flyer
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F1wanabe
I believe its the drag the wings are producing. Look at the slowest- the f22- with a long wing which includes a large lerx area way back to the rear of the wing and you see a long wing root. The F18 has the shortest wing root. The F15 is also pretty short and the mig is essentially a delta with a tail. It's also interesting that the f22 as a parkjet is one of the easiest to fly given the larger wing area, and the f18 is one of the more edgy planes to fly. So for parkjets, which are meant to fly in a park, I am happier with the performance of a slower plane with larger wing area than a faster plane with a lower wing area! But flying the slowest plane doesn't sound very exciting, does it?
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F1wanabe
Just checked and yes, the real f22 has an 840 Sq ft wing area vs the f18 which has a 400 Sq ft wing area. I'm sure that this ratio is transferred to the parkjet plan as well. The f22's engines are beasts and can push thru that drag on the real plane whereas you have the same power system on the parkjets. Interesting tests! FYI, I think the f15 is one of the best flying parkjets I've flown. Stable like the F22 and maneuverable like the mig 29. It happens to fall right in the middle of your speed tests too!
Check out this image which clearly shows the different in wing area from slowest to fastest...


Sent from my SM-N950U using Tapatalk
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OldSchoolFlyer
Thanks for the reply and analysis of my speed info. Clearly the F-18 wing area is much less than the F-22 which explains why the F-18 is so fast. I agree with your opinion of the F-15. The F-15 is my favorite and probably the best RCP park jet. I am going to cut 2" off the wings of the F-18 down to 28" span and see if I can get up to 70 mph.
Old School Flyer
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Wildthing
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Lots of variables ESC Motor age and settings. I wil try to narrow the variables and continue to compare the speeds. Thanks
Swap the whole power setup including rx and see what happens.
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Wildthing
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I believe its the drag the wings are producing. Look at the slowest- the f22- with a long wing which includes a large lerx area way back to the rear of the wing and you see a long wing root. The F18 has the shortest wing root. The F15 is also pretty short and the mig is essentially a delta with a tail. It's also interesting that the f22 as a parkjet is one of the easiest to fly given the larger wing area, and the f18 is one of the more edgy planes to fly. So for parkjets, which are meant to fly in a park, I am happier with the performance of a slower plane with larger wing area than a faster plane with a lower wing area! But flying the slowest plane doesn't sound very exciting, does it?

You know the faster you go the less it hurts.
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