This photo of Tom Aberle's 284 mph modified Mong Sport “Phantom” from the KITPLANES site got me thinking again about inverted gull wings. The configuration brings to mind everything from Neal Loving's "Loving's Love" classic homebuilt racer to Richard Vought's prototype Blohm & Voss Ha 137 prototype attack aircraft to the legendary Vought F4U "Corsair" to name just a few.
For a small, single-seat or two-seat light aircraft, the inverted gull wing does seem to offer a few advantages:
- Lower drag for main gear installation compared to wing-mounted gear on a straight low wing or fuselage-mounted gear
- Better downward visibility compared to a straight low wing
- Likely a good arrangement for building and/or storage in a small space since it naturally suggests a three-piece wing
- Natural fit for upward-folding wings since it lowers the overall height of the installation, might also work for straight horizontal folding since it puts the wing under the rear fuselage.
- Distinctive cool looks!
There are also some obvious disadvantages:
- Some loss of efficiency (increased drag) vs. a straight wing of identical area
- Reduced ground clearance so definitely not the right arrangement for off-airport, rough field operations
- Pretty much requires wing-mounted gear, which may not be desirable in many applications
- Upward-folding would limit maximum span to about 20' to keep folded width and height down and so require a quite low aspect ratio. For example, a 20' span and 4.5' chord would give 90 sq ft of wing area and an aspect ratio of 4.4.
Other pros and cons come to mind? Other successful or unsuccessful examples of inverted gull wing light aircraft to share?
Cheers,
Matthew