Schreder HP-18

From Wikipedia, the free encyclopedia

You have new messages (last change).
Schreder HP-18
Type designation HP-18
Designer Richard Schreder
Competition class Club (formerly 15 metre)
Crew 1
Length 22.8 ft (6.95 m)
Height
Cockpit width
Cockpit height
Wingspan 49.2 ft (15 m)
Wing area 113 ft² (10.5 m²)
Aspect ratio 21.4
Wing profile Wortmann FX 67-K-170
Empty mass ca. 470 lb (213 kg)
Water ballast 200 lb (90 kg)
Maximum mass 970 lb (440 kg)
Wing loading 8.58 lb/ft² (41.9 kg/m²)
Maximum speed knots ( km/h)
Maneuver speed knots ( km/h)
Speed in strong
turbulence		 knots ( km/h)
Minimum sink rate ca. 110 ft/min (0.55 m/s)
Best glide ratio ca. 40 at knots ( km/h)


The HP-18 is a Richard Schreder-designed metal Racing Class sailplane that was offered as a kit for homebuilding during the 1970s and 1980s. It is one of the most successful of all North American homebuilt aircraft in terms of number built, with over one hundred kits sold and many completed.

Contents

[edit] Description

The ship has a forward fuselage of fiberglass and a sheet metal rear fuselage. The wing is built up from a metal spar with foam ribs to which the aluminum skin is bonded. This 15 m racing class ship carries water ballast inside the wing box spar, features flap-aileron coupling and has 90 degree deflecting flaps to permit steeper landing approaches and lower, safer touchdown speeds. The control stick is side-mounted with attached brake handle and trim tab although modifications using a conventional stick have been made.

Major features:

  • Very low cockpit with reclining seating position
  • Sidestick (changed to conventional stick by some homebuilders)
  • Two-piece canopy (changed to single piece forward opening by some homebuilders)
  • V-tail that folds upwards for easy storage
  • Wing structure composed of spars with caps pre-machined from solid aluminium plate and aluminium wing skins bonded to closely spaced foam ribs
  • Fiberglass fuselage pod, wing tip skids and tail fairings
  • Aluminium tail cone
  • Winglets added by some homebuilders
  • Water ballast carried inside the hollow aluminium wing spars
  • Typical Schreder trailing edge flaps/airbrakes partially interconnected with the ailerons


[edit] Variants

As most homebuilts, the HP-18 has been constructed with many variations in detail. Perhaps the most significant version is the HP-18W developed by Canadian Udo Rumpf, which features a modified wing airfoil, winglets, a front-hinged canopy, conventional control stick and higher ballast capacity.

[edit] Designation series

HP-7 - HP-8 - HP-10 - HP-11 - HP-12 - HP-13 - HP-14 - HP-15 - HP-16 - RS-15 - HP-17 - HP-18 - HP-19 - HP-20 - HP-21 - HP-22

[edit] Sources

Retrieved from "http://en.wikipedia.org../../../s/c/h/Schreder_HP-18_0148.html"