Soaring November 1993
The High Performance (HP) 7, build in 1957, was the first sailplane built by
Dick Schreder. Although it had barely been test flown he placed well with it
during the U.S. Nationals. The HP-7 was destroyed in an aerotowing accident.
Technical Details (not available)
The HP-8 was an improved version of the HP-7 built in 1958. With this aircraft
Dick won the 1958 and 1960 U.S. National. He also set world records with it
in all three speed categories in 1959, and two of these were raised again by
the same ship flown by George Moffat (Soaring, Oct. '62, p. 10). Like most Schreder
designs it featured a high wing loading which improved it's performance at high
speeds. The HP-8 was purchased from Moffat by Fred Hefty and John Elizalde and
donated to the National Soaring Museum.
Technical Details
L/D max: 37 @ 58.2 kts, 67 mph, 108 Km/h
Min. Sink: 2.2 fps @ 57 mph,
1.30 kts @ 49.5 kts,
.67 m/s @ 92 Km/h
Span: 51.4 ft, 15.7 meters
Area: 110 sq.ft, 10.22 sq.meter
Aspect Ratio: 24
Empty weight: 618 lbs, 280 Kg
Gross weight: 850 lbs, 385 Kg
Wing Loading: 7.53 lbs/sq.ft, 37.7 Kg/sq.meter
Airfoil: NACA 65 (3)-618
Note: The published min. sink and speed yields a L/D of 38 which is not consistent
with a L/D max of 37.
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The HP-9 was unique among Dick Schreder's designs. It was intended to participate
in the Standard Class at the 1960 Internationals; however, it was not completed
in time. Among it's unique features is a standard tail with an all-moving horizontal
stabilizer; fowler flaps which increased the wing area to 143.7 sq. ft. (13.3
sq. meters) when extended reducing the sink to 2.11 fps @ 47 mph (40.8 Kts,
76 Km/h) ; and, dive brakes. Only one was built and it is still active.
Technical Details
L/D max: 36 @ 54.3 kts, 62.5 mph, 100.6 Km/h
Min. Sink: 2.26 fps @ 60 mph,
1.33 kts @ 52.1 kts,
.69 m/s @ 97 Km/h
Span: 48.84 ft, 15 meters
Area: 127.4 sq.ft, 11.83 sq.meter
Aspect Ratio: 18.6
Empty weight: 650 lbs, 294 Kg
Gross weight: 845 lbs, 382 Kg
Wing Loading: 5.54 lbs/sq.ft, 32.3 Kg/sq.meter
Airfoil: Wortmann FX-191
Note: The published min. sink and speed yields a L/D of 39 which is not consistent
with a L/D max of 37.
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The HP-10 was developed by Dick Schreder who built a prototype and flew it in
the 1961 U.S. Nationals winning the Stroukoff Trophy for a 35.5-mph (30.8 kts,
57.2 Km/h) 142-mile (132.4 nm, 228.7 Km) Goal and Return. Helisoar (Steve du
Pont) bought the production rights and manufactured a number of kits before
discontinuing production. (Without being able to include pilot Schreder in the
kit, the HP-10 developed a reputation of being difficult to keep aloft in weak
conditions.) The constant-cord aluminum honeycomb wing is unique on Schreder
aircraft, and the design features 34-ft span flaps and the familiar Schreder
Vee- tail. Some ships were modified with fiberglass Hoerner wingtips made available
by Helisoar. When du Pont liquidated Helisoar he donated the entire physical
tooling, kit parts, inventory, engineering reports and production drawings to
the EAA Museum, since the SAA had no place for the material at the time.
Technical Details
L/D max: 35 @ 52.1 kts, 60 mph, 97 Km/h
Min. Sink: 2.2 fps @ 43 mph,
1.30 kts @ 37.4 kts,
.67 m/s @ 69 Km/h
Span: 48 ft, 14.6 meters
Area: 113 sq.ft, 10.5 sq.meter
Aspect Ratio: 20.2
Empty weight: 534 lbs, 242 Kg
Gross weight: 780 lbs, 353 Kg
Wing Loading: 6.75 lbs/sq.ft, 33.6 Kg/sq.meter
Airfoil: NACA 65 (3)-618 mod.
Note: The published min. sink and speed yields a L/D of 28.7.
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Still dreaming of the perfect sailplane, Dick Schreder turned tout the HP-11
in 1962 in time for the U.S. Nationals, in which he placed third and made the
longest flight, 469 miles (755 Km). He later placed third in the 1963 World
Championships, where he made a 382-mile (332 km, 615 Km) flight. Plans for an
improved version, the HP-11a with retractable wheel were sold, as were numerous
kits, until production switched over to the HP-14.
Technical Details
L/D max: 37 @ 47.8 kts, 55 mph, 89 Km/h
Min. Sink: 1.8 fps @ 50 mph,
1.07 kts @ 43.5 kts,
.55 m/s @ 80.5 Km/h
Span: 52 ft, 15.8 meters
Area: 104 sq.ft, 9.66 sq.meter
Aspect Ratio: 26
Empty weight: 400 lbs, 181 Kg
Gross weight: 650 lbs, 294 Kg
Wing Loading: 6.25 lbs/sq.ft, 30.4 Kg/sq.meter
Airfoil: NACA 65 (3)-618
Note: The published min. sink and speed yields a L/D of 40.6 which is not consistent
with a L/D max of 37.
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The HP-12A is a traveling sailplane: the fuselage was begun by Art Heabener
in New Jersey, the wings by Tom Hall in Florida. The project went with Hall
to California and then to Illinois, where Rudy Dunda and Bill Carson bought
it in 1977. One year later it was flying. The paperwork identifies the ship
as HP- 12A, because its parts have the following pedigree: wings, HP-14; tail,
HP-18; rear fuselage, HP-11; forward fuselage, HP-10. Despite the confusion
about the number, the HP part is unmistakably Dick Schreder. It is important
not to confuse this ship with the genuine HP-12, which was a one-of-a-kind built
to fly in the 1965 World Championships in England and destroyed in a crash when
John Karlovich had to bail out over Marfa, Texas, during the 1972 Standard Class
Nationals after suffering a structural failure. (Soaring, Sept. '72, p.36.)
That bird is the real HP-12 and is not directly related to the hybrid version
described here.
Technical Details
L/D max: 39 @ 47.8 kts, 55 mph, 89 Km/h
Min. Sink: 1.8 fps @ 47 mph,
1.07 kts @ 40.8 kts,
.55 m/s @ 76 Km/h
Span: 54.6 ft, 16.6 meters
Area: 138.3 sq.ft, 12.85 sq.meter
Aspect Ratio: 21.6
Empty weight: 525 lbs, 238 Kg
Gross weight: 755 lbs, 342 Kg
Wing Loading: 6.25 lbs/sq.ft, 26.6 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.
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The HP-13 is essentially an HP-11 fuselage with the Wortmann airfoil used on
the HP-12 with an extended span. It was and intermediate step in the development
of the HP-14. A total of eight were built.
Technical Details (not available)
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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 @ 47.8 kts, 55 mph, 89 Km/h
Min. Sink: 1.8 fps @ 47 mph,
1.07 kts @ 40.8 kts,
.55 m/s @ 76 Km/h
Span: 54.6 ft, 16.6 meters
Area: 138.3 sq.ft, 12.85 sq.meter
Aspect Ratio: 21.6
Empty weight: 464 lbs, 210 Kg
Gross weight: 728 lbs, 329 Kg
Wing Loading: 5.26 lbs/sq.ft, 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 @ 47.8 kts, 55 mph, 89 Km/h
Min. Sink: 1.7 fps @ 46 mph,
1.0 kts @ 40 kts,
.52 m/s @ 75 Km/h
Span: 59 ft, 18 meters
Area: 146 sq.ft, 13.56 sq.meter
Aspect Ratio: 23.8
Empty weight: 484 lbs, 219 Kg
Gross weight: 755 lbs, 342 Kg
Wing Loading: 5.1 lbs/sq.ft, 25.2 Kg/sq.meter
Airfoil: Wortmann FX 61-163
Note: The published min. sink and speed yields a L/D of 40 which is optimistic
for a L/D max of 41.
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The original HP-15 had an extreme 33-1 aspect ration. It was built to fly in
the 1969 U.S. Nationals. When Dick Schreder placed 65th he decided a major redesign
was called for, so the wing of the ship was "retired" and the fuselage was eventually
acquired by John Apps, who said it was one of the few fuselages available that
would accommodate his six feet four inches. In 1973 Apps bought a HP-16 wing
kit and began to build a new set of wings for the -15. The aircraft is owned
by Stephen Grube. A second HP-15 was built by Robert Brown which has HP-18 wings.
Technical Details
L/D max: 45 @ 47.8 kts, 55 mph, 89 Km/h
Min. Sink: 1.6 fps @ 45 mph,
.95 kts @ 39.1 kts,
.49 m/s @ 72 Km/h
Span: 49.2 ft, 15 meters
Area: 75 sq.ft, 6.97 sq.meter
Aspect Ratio: 33
Empty weight: 330 lbs, 149 Kg
Gross weight: 600 lbs, 271 Kg
Wing Loading: 8.0 lbs/sq.ft, 38.9 Kg/sq.meter
Airfoil: Schreder 68-180
Note: The published min. sink and speed yields a L/D of 41.
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Dick Schreder briefly interrupted the HP numbering system for his designs to
label the RS-15 with his own initials and the metric wingspan of the design.
It is an innovative pod-and-boom design which originally was intended to convert
into various configurations, with wingspans of from 13 to 20 meters being matched
with booms of suitable lengths, two-place pods, etc. In the event, Dick decided
to go with only the basic 15 meter sing- seat version, which features a fiberglass
cockpit pod and a six- inch-diameter aluminum tube for the boom. These were
supplied for the same cost as a conventional fuselage, but required several
hundred fewer hours to build. The wing is that used for the HP-16. It can carry
up to 200 lbs. (90.5 Kg) of water ballast.
Technical Details
L/D max: 38 @ 50.4 kts, 58 mph, 93 Km/h
Min. Sink: 2.1 fps @ 50 mph,
1.24 kts 43.5 kts,
.64 m/s @ 80.5 Km/h
Span: 49.2 ft, 15 meters
Area: 113 sq.ft, 10.5 sq.meter
Aspect Ratio: 21.5
Empty weight: 440 lbs, 199 Kg
Gross weight: 940 lbs, 425 Kg
Wing Loading: 6.5 to 8.3 lbs/sq.ft,
31.8 to 40.5 Kg/sq.meter
Airfoil: Wortmann 67-150
Note: The published min. sink and speed yields a L/D of 35.
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The HP-16 design by Dick Schreder involved major changes in Schreder's Standard
Class design, with a completely different wing of much lower aspect ration and
much greater area. The aluminum wing skins are bonded to foam ribs, reducing
rivet use and construction time. The HP-16 retains the usual 90 degree flaps
so beloved of pilots who need to squeeze into tight quarters in off-field landings.
It can carry up to 200 lbs (90.5 kg) of water ballast.
Technical Details
L/D max: 36 @ 47.8 kts, 55 mph, 88.5 Km/h
Min. Sink: 2.16 fps @ 50 mph,
1.28 kts @ 43.5 kts,
.66 m/s @ 80.5 Km/h
Span: 49.2 ft, 15 meters
Area: 113 sq.ft, 10.5 sq.meter
Aspect Ratio: 21.5
Empty weight: 424.5 lbs, 192 Kg
Gross weight: 924.5 lbs, 418 Kg
Wing Loading: 6.4 to 8.1 lbs/sq.ft,
31.2 to 39.8 Kg/sq.m
Airfoil: Wortmann 67-150
Note: The published min. sink and speed yields a L/D of 34.
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Another Dick Schreder one-of-a-kind was the HP-17, which was basically an experiment
to test a then-new Wortmann high-lift, low-drag airfoil. The ship also featured
a wing spar which carried water ballast inside it, full-span flaps and spoilers
for ailerons. The value of the experiment was more or less evident after Dick
finished 38th in the 1973 Standard Class U.S. Nationals. The design was a dead
end in the face of the far more successful design which next appeared on the
Schreder drawing board. It can carry up to 200 lbs (90.5 Kg) of water ballast.
Technical Details
L/D max: 40
Min. Sink: 1.7 fps @ 40 mph,
1.0 kts @ 34.8 kts,
.52 m/s @ 64 Km/h
Span: 49.2 ft, 15 meters
Area: 113 sq.ft, 10.5 sq.meter
Aspect Ratio: 21.4 Empty weight: 440 lbs, 199 Kg
Gross weight: 940 lbs, 425 Kg
Wing Loading: 6.5 to 8.3 lbs/sq.ft,
31.8 to 40.5 Kg/sq.meter
Airfoil: Wortmann FX 61-163
Note: The published min. sink and speed yields a L/D of 35.
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The HP-18 is one of the most successful of all U.S. homebuilt sailplanes in
terms of numbers built: more than 180 kits were sold worldwide, about 50 of
them to builders in Canada, Israel, Australia, New Zealand, Finland, Norway,
Argentina, Mexico and Germany. More than 50 of them are flying in the U.S.,
and others pop out of garages with each new soaring season. 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-Meter Class ship carries 200 lbs (90.5 Kg) of water ballast inside the wing
box spar, features flap-aileron coupling and retains the popular 90 degree flap
deflection to permit steeper landing approaches and lower, safer touchdown speeds.
The control stick is side-mounted with attached brake handle and trim tab.
Technical Details
L/D max: 40
Min. Sink: 1.8 fps @ 50 mph,
1.07 kts @ 43.5 kts,
.55 m/s @ 80.5 Km/h
Span: 49.2 ft, 15 meters
Area: 113 sq.ft, 10.5 sq.meter
Aspect Ratio: 21.4
Empty weight: 470 lbs, 213 Kg
Gross weight: 970 lbs, 425 Kg
Wing Loading: 6.8 to 8.58 lbs/sq.ft,
31.8 to 40.5 Kg/sq.meter
Airfoil: Wortmann 67-150
Note: The published min. sink and speed yields a L/D of 40.6 which is not consistent
with a L/D max of 40.
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The HP-19 had the apparent misfortune to reach completion just about the time
Dick Schreder got the idea for a better sailplane. One hardly can quarrel with
a ship which offers an L/D of 42, but any designer in the world would drop 42
to hotfoot toward 48, 52 or even 62 if he thought he could do it. As soon as
Dick Schreder completed the drawings for the -19 and its sister ship the - 20
he submerged himself in development work on the HP-21, and only the prototypes
of the -19 and-20 exist. Heinrich Preiss built the sole -19 at Schreder's shops
in Bryan, Ohio and flew it until he sold it to Frank Wright. It features a straight
tapered wing employing a Schreder modification of the Wortmann airfoil and winglets.
The ship has a T-tail configuration, large flaps provide glidepath control,
and it carries 200 lbs (90.5 Kg) or water ballast.
Technical Details
L/D max: 42 @ 43.5 kts, 50 mph, 80.5 Km/h
Min. Sink: 1.6 fps @ 40 mph
.95 kts @ 34.8,
.49 m/s @ 64 Km/h
Span: 49.2 ft, 15 meters
Area: 113 sq.ft, 10.5 sq.meter
Aspect Ratio: 21.4
Empty weight: 470 lbs, 213 Kg
Gross weight: 970 lbs, 439 Kg
Wing Loading: 6.8 to 8.58 lbs/sq.ft,
33.2 to 41.8 Kg/sq.meter
Airfoil: Wortmann/Schreder mod.
Note: The published min. sink and speed yields a L/D of 36.6.
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While he was building the fuselage for the HP-19 Dick Schreder doubled everything
and built a duplicate, on which he put a different set of wings to produce the
HP-20. The -20's lift comes from a double-tapered planform wing using another
Schreder modification of a Wortmann airfoil (he calls it Schreder 3). Although
the 15 meter span is the same as the -19 the HP-20's area is less and its loading
is significantly higher. Thus although both machines have an L/D of 42, the
speed at which the -20 yields this figure is a full 10 mph higher than that
of the - 19. Like the - 19, the -20 is a one-of-a-kind machine. The structure
of the 20 is all metal with foam ribs, it carries 200 lbs (90.5 Kg) of water
ballast, features winglets, and a T-tail configuration.
Technical Details
L/D max: 42 @ 52.1 kts, 60 mph, 97 Km/h
Min. Sink: 2 fps @ 50 mph,
1.18 kts @ 43.5 kts,
.61 m/s @ 80.5 Km/h
Span: 49.2 ft, 15 meters
Area: 102 sq.ft, 9.48 sq.meter
Aspect Ratio: 24.5
Empty weight: 470 lbs, 213 Kg
Gross weight: 970 lbs, 439 Kg
Wing Loading: 7.5 to 9.5 lbs/sq.ft,
36.7 to 46.3 Kg/sq.meter
Airfoil: Wortmann/Schreder mod.
Note: The published min. sink and speed yields a L/D of 36.9.
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