Schreder HP-11

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**Schreder HP-11**

Type designation	HP-11
Competition class	Club
Number built	73 +
Crew	1
Length
Height
Cockpit width
Cockpit height
Wingspan	15.85 m (52 ft)
Wing area	9.66 m² (104 ft²)
Aspect ratio	26
Empty mass	204 kg (450 lb)
Water ballast	NA
Maximum mass	318 kg (700 lb)
Wing loading	6.7 lb/ft²
Maximum speed	130 kt/150 mph/240 km/h
Rough air speed	105 kt/121 mph/194 km/h
Maneuver speed	105 kt/121 mph/194 km/h
Minimum sink rate	0.55 m/s (1.8 ft/s) at 47 mph (75 km/h)
Glide ratio	37:1 at 86 km/h (54 mph)
Roll rate

The Schreder HP-11 is a glider designed by Richard Schreder in 1962.

The ‘11 thermals best in the high 40s. Below that, reduced aileron authority gives you a real workout in rough thermals. Above that, you start losing out on the polar.

It uses about 10 degrees of flaps in most thermals. With the stock 18-tooth flap gear, that’s about a quarter turn. In tight thermals, use the next notch beyond a quarter turn, and work hard to keep the speed around 48 knots (89 km/h). In looser thermals, use one notch before a quarter turn, and let the speed run up to 52 or 54 knots.

Best glide is probably around 50-52 knots, but one should never fly that slow when going straight. On any reasonable day, there’s little point in going any slower than about 65 knots, try to bash along at 75+ knots.

The NACA 65(sub3)618 airfoil has a rather narrow drag bucket, so the HP-11 really rewards attention to the flap setting. When cruising, I use 0 flap at 60 knots, -10 degrees at 110 knots, and vary the settings linearly in between those speeds.

The real surprising thing about the HP-11 is how well it runs in the range of 70 to 90 knots. With good attention to the flap setting, you can almost keep with the glass guys in those speeds. Above that, they will get away, but you can usually keep them in sight. And when you get to the next thermal, the ‘11’s light weight will let you climb with or away from them. It is a high data point on the bang-for-the-buck curve. And you can paint it any color you want!