Mini hawk pusher - tip stall issue - RC Groups
Thread Tools
May 09, 2012, 10:59 AM
Registered User

Mini hawk pusher - tip stall issue

I built a mini hawk for fun and it flies really well except for one problem. It has a nasty tip-stall issue when slowing down for a landing. The model is based on a 3-view drawing and is 100% scale in terms of overall size. The wing is a flat bottom with a basic airfoil sanded on the top. Where should I start to look to resolve the issue.
Sign up now
to remove ads between posts
May 09, 2012, 05:31 PM
Registered User


May 10, 2012, 12:40 AM
Zen in the art of foam
djacob7's Avatar
It's not a glider, so you must land at relatively high speed. One wing will naturally stall before the other. If you really want to come in slower, you might try twisting the wing tips leading edge downwards.
May 10, 2012, 05:25 AM
Gravity Sucks
Hi gdimonte,

being a jet and since you have indicated that you used scale proportions, this will likely be an airspeed thing as mentioned above. A sanded airfoil may not produce sufficient lift at low (or even just reduced) airspeeds. You may need to review your wing (span, area and/or airfoil). Also with a pusher config, keep in mind you won't havethe prop blowing air over the wing and helping to generate lift. Are your controls mussy on approach?

Lots of the hawks modelled have an enlarged (i.e. non-scale) wing to achieve suitable flying characteristics. Also, the real hawk has wing fences on the LE about 2/3 of the way out. My understanding is that they work to stop exactly the type of thing you are descibing.

Try having a look at these 2 threads by Nitro.

He has a fantastic looking and flying mini EDF hawk. He has a built up airfoil and has the wing fences. I think his wing may have been enlarged too (IIRC).

Good luck with it. It's a great looking little model and hope you get it sorted. If nothing else, just fly it WOT and like you stole it - that should fix things!
May 10, 2012, 04:36 PM
Registered User
Thanks for the input. I'm going to play around with a larger wing area and see what I get. In the mean time, I'm going to knock-off a couple of airframes to play with.

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Idea Solution to vicious tip stall! skybolt123 Electric Plane Talk 91 May 15, 2012 11:30 AM
Discussion washout at wing tips to avoid stall phil alvirez Scale Sailplanes 36 May 12, 2012 05:12 AM
Question Graupner Mini Discus TIP STALL????? Edwinzea Foamies (Kits) 4 Feb 15, 2010 02:19 PM
Discussion GP Mini Super Sportster: Tendency to tip stall? whwong Parkflyers 0 Apr 25, 2006 11:17 AM
Tip Stall - Mini Thermalaire sierra-gold Electric Sailplanes 4 Sep 26, 2003 08:21 AM