The Schreder / Slingsby HP-14

a free plan for a scale model
by Jim Owen

This is not inteneded as documentation for the HP-14 as this has been adequately covered in depth by Soar Idaho. If that article should disappear from the internet, you can download a pdf copy here

In support of this article, Jim Owen has kindly donated his drawings for a scale model of the HP-14 in both the V-tail and T-tail versions of the glider and are available for download from this site further down the page.

A Brief History of the HP-14

"In the HP-14 Dick Schreder made improvements to he HP-11/13 fuselage. The Wortmann airfoil wings were mated to the improved fuselage. In the HP-14 Dick Schreder used lower wing loading and reduced aspect ratio, aiming to create a potent Open Class sailplane that would do well in weak conditions. He succeeded admirably: more than 40 all versions were built in the U.S. and Slingsby in England. The ship has appeared with all three tail styles: the original had the familiar Schreder Vee-tail, Slingsby produced the C version with conventional tail, and the final T version used the C wing and a T-tail appeared in 1968. Slingsby HP-14's received type certificates and are licensed in the standard category; the rest are experimental. Hp-14's are famous for the effectiveness of their flaps for landing, and Schreder produced them in kit form from 1966 to 1970. "

Technical Details - HP-14
L/D max: 39 @ 89 Km/h
Min. Sink: .55 m/s @ 76 Km/h
Span: 16.6 meters
Area: 12.85 sq.meter
Aspect Ratio: 21.6
Empty weight: 210 Kg
Gross weight: 329 Kg
Wing Loading: 25.6 Kg/sq.meter
Airfoil: Wortmann FX 61-163

Note: The published min. sink and speed yields a L/D of 38 which is optimistic for a L/D max of 39.

Technical Details - HP-14T
L/D max: 41 @ 89 Km/h
Min. Sink: .52 m/s @ 76 Km/h
Span: 18 meters
Area: 13.56 sq.meter
Aspect Ratio: 23.8
Empty weight: 219 Kg
Gross weight: 342 Kg
Wing Loading: 25.2 Kg/sq.meter
Airfoil: Wortmann FX 61-163

Click the above for a Gallery of images

Jim Owen's plan is now available in PDF fromat for both the V-Tail and T-Tail versions.
Click the image below to go to the download section