Shorts Skyvan Floatplane in RAMC service

[Weaver]

That looks very chunky and purposeful in the stripey cammo: I'd be inclined to call it the 5-Ton Frog.... Well done! 

Re Skyvan stats:

Skyvan series 3
Wing area: 378 sq ft
Empty weight: 7350 lb
Power: 2 x 715 hp
Cruise speed: 170 kt

Twin Otter (series 400)
Wing area: 420 sq ft
Empty weight: 6900 lb
Power: 2 x 750 hp
Cruise speed: 150 kt

So the Twin Otter has roughly 11% more wing area than the Skyvan, and is roughly 11% slower: just what you'd expect. The Twotter's extra power and lower weight is probably offset by the inherent efficiency of the Skyvan's higher-aspect-ratio wing.

[AS.12]

In addition to the area of the aerofoil struts, the Skyvan's fuselage was a lifting-body that allegedly compensated for its own structural weight.

Re: Ansett in PNG.  The switch from Astazou 12 to TPE331 was prompted by the former's inability to achieve its rated output in trials in New Guinea for Ansett-MAL*.  This lost Shorts the sale, and for the same reason an Italian airline ( Aeralpi** ) switched to the Twotter when the Astazou proved gutless in the Dolomites. 

An interim concept in early 1967 was to adopt the PT6A-27. Had Shorts chosen the PT6 or Garrett immediately after the piston engine then history might have been more generous to the Skyvan.

The Skyvan was originally planned with a tri-phibian undercarriage of wheels, floats or skis but I don't believe the latter two were ever fitted or tested, though were mentioned in early advertising.


* Anset-MAL and Papua Airlines took one, VH-PNI, and cancelled four without penalty due to inability to perform
** Aerapli took both Skyvans that they had ordered, I-CESA and I-TORE.  They wrote-off the latter in fog at Venice and Shorts repossessed CESA in 1969