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I recently came across the Dyke Delta, designed by John Dyke. It is a delta wing (more like diamond planform) homebuilt. I'm curious about how this airplane handles, considering delta wings have some particularities.

Specifically:

  1. How does the Delta Dyke achieves pitch stability, without an horizontal stabilizer? Most delta wing airplanes have long chord wings, so a little elevon trim can be used, but the Dyke has short chord wings, so is pitch stability a problem?

  2. Does it have flaps? If so, how effective are they, would they interfere with the pitch attitude?

  3. Delta wings are notorious for high take-off and landing speeds, because they generate less lift at low airspeeds. This is usually made up for with vortex lift created by by an aggressive angle of attack, like Concorde. But as far as i've seen, that doesn´t happeb with the Dyke. So how does it handle short take-off/landing with a normal angle of attack?

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How does the Delta Dyke achieve pitch stability?

See the rear part of the wing as an elevator which happens to be attached to the wing. The elevons are trimmed slightly trailing edge up, so this rear part produces less lift per area than the forward part. Stability is achieved naturally as explained here.

Does it have flaps?

No, flaps would increase lift per area at the rear wing and make the plane unstable. Only leading edge devices are possible in tailless designs with little sweep, but not employed in the Dyke Delta. With enough wing sweep, flaps can be used inboard but must be combined with more trailing edge up trim on the outer, more rearward wing. See the Horten IX / Go-229 for an example with inboard flaps.

Delta wings are notorious for high take-off and landing speeds ... So how does it handle short take-off/landing with a normal angle of attack?

as the linked Wikipedia article explains:

Its stall speed (70–75 mph) is relatively high for a small single-engine aircraft, and its configuration at touchdown is relatively nose-high. Approach speeds of 100–110 mph are used.

Being an experimental design, the Dyke Delta does not need to conform to FAR 23 which demanded a minimum speed no higher than 61 knots. It basically skirts the rules to allow for a higher landing speed and lower pitch attitude during landing. Still, the low aspect ratio results in a fairly high nose-up attitude.

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  • $\begingroup$ The thing could do 180mph on 180 hp, pretty impressive for a 4 place airplane. But too many negatives to get more than a few builders keen on the funky looks interested. I +3 seating, can't see the ground from the pax seats, the fast landing speeds. Just too much of an oddball. A BD-4 was a more practical contemporary choice, $\endgroup$
    – John K
    Commented Jun 8 at 3:38
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    $\begingroup$ @JohnK The 3rd passenger had to be small to fit on the rear bench, so not a real 4-place airplane. And a high top speed is easier when you keep wing area too small for 61 knots - Rutan used the same tricks. $\endgroup$
    – Peter Kämpf
    Commented Jun 8 at 5:42

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