Construction Tips/Pitfalls/Modifications/Etc.
June 15, 2014

HP-18, RS-15 Kits, Parts, and HP-11/HP-14 plans. Some spare parts for earlier HP-series sailplanes also in stock. For more information, contact Bob Kuykendall at (Updated 9/3/99)

Super HP-18 female molds. Nose mold and Turtle Deck mold for modifying the standard HP-18 into the Super HP-18. Molded parts from molds provide a more comfortable upright seating configuration similar to current sailplane designs. The molds are owned by Chris Esselstyn; however, he is willing to loan them to other builders. The molds are currently in Manassas, VA. If you would like to use the molds contact Dustin via email. (Updated 6/15/14)


Glider Trailer Design & Building - Adelaide University Gliding Club (Updated 1/15/05)
Building the Cigar Tube Trailer - by Alex Upchurch (Updated 11/29/99)


Weight & Balance Fuselage Leveling Wedge by Wayne Paul Added (1/15/12)
"Why is White Sacred?" paraphrased by Bob Whelan Added 3/24/07)
JAR-22 "Sailplanes and Powered Sailplanes" - provided by Judah Milgram (Added 3/13/06)
Can I Build an HP Glider from Scratch? - by Bob Kuykendall (Updated 8/16/99)
Ballistic Recovery System (BRS) - by Jim Harper (April 17, 2003)
HP-14 News Letters, and Weight & Balance - by Dick Schreder (2/18/98)
The Material…Rigicell - Sport Aviation 1972. (Updated 4/23/98)
Home-Builders' Hall - by Stan Hall (Updated 2/4/00)
RS-15 & HP-16 News Letters
Safety Bulletins - (Added 12/16/97)
HP-11 Advisory: sheared rivets in wing root reinforcing strap - by Bob Kuykendall (Added 7/29/03)
HP-11 Modifications - (Added 12/18/97)
What's this AC 43.13 Thing? - by Bob Kuykendall (8/26/99)
HP Parts Naming Convention - By Bob Kuykendall (9/13/00)
US Homebuild Regs Update - from EAA (10/6/01)
Hydraulic Flaps Part 1 and Part 2 - by Stan Hall (Updated 1/19/02)
Inspection Guidelines - by Bob Kuykendall (5/10/02)
A Lumbar Support that Works - by Tony Burton (1/25/03)
Instrument that reads drag! - by Richard H Johnson (2/8/03)
Rivet Cross-reference - by Bob Kuykendall (Added 3/28/03)
Flap Drive Service Bulletin (7-1-86) - by Brian Aircraft, Inc. (Added 3/30/03)

Convenient Aides / Assembly Tools

Hydraulic Trailer Ramp Scissors Jack - by Udo Rumpf (Added 12/3/08)
One Man Assembly System - by Hugh Helmick (6/17/98)
Tail Dolly Construction - by Wayne Paul (3/1/09)
LTW-3 Wing Transporter
- Sailplane Builder - May-June 2002
Laser Wing Alignment - by Hugh Helmick (8/31/00)
V-Tail Rigging Fittings - by David Severns (6/9/02)
Wing Assembly Draw Bar - by Udo Rumpf (11/12/08)
Fuselage "T" Bar - by Udo Rumpf (11/13/08)
HP-14 Fuselage "T" Bar - by Wayne Paul (Added 03/21/09)

Construction Photos

N5578V -- C-FAXH -- N9029U


Super HP-18 Fuselage Modification Modes - by Chris Esselstyn (added 1/29/13)
Fuselage Damage Repair - by Brian Case (Added 01/03/12)
RS-15 Oxygen Bottle Installation - by Tony Burton (added 05/15/09)
V-tail Fairing Costruction - by Tony Burton (added 06/14/06)
Fiberglass Turtleback Construction - by Wayne Paul (Added 5/12/08)
Paul Bikle HP-14 Flap Actuation System - by Graeme Rickert (Added 03/06/06)
Picture and Drawing of Bell-Crank Mod for HPs with HP-18 Wings
- by Jim Collins (Added 03/07/06)

HP-14 Landing Gear Gas Spring Retrofit
- by Wayne Paul (Added 02/29/04)
Adding Adjustable Rudder Pedals to the HP 14 - by John de Jong (Updated 04/23/11)
How the HP Belly Skins Got Their Curve - by Bob Kuykendall (Updated 5/28/99)
HP-14 Pneumatic Tailwheel Installation - by Wayne Paul (Added 01/14/09)
SHP-18 Tail Wheel Installation - by Udo Rumpf (4/27/98)
HP-18k Center Stick Design - by Bob Kuykendall (Updated 7/9/01)
HP-16 Center Stick Modification - by Brian Case (Updated 2/9/01)
Strut Overhaul and Servicing - by Wayne Paul (Updated 12/11/13)
Brake/Wheel Source - by Udo Rumpf (Updated 7/14/99)
Drum Brake Parts - by Wayne Paul (Added 11/7/11)
Friction Brake Lining Replacement - by Bob Kuykendall (Added 10/8/01)
HP-18 Brake and CG Hook - by Udo Rumpf (Updated 8/26/99)
Your Brake Installation - Sport Aviation - (Added 10/15/03)
Cable Fabrication Source - (Updated 1/4/00)
SHP-18 Center Stick Installation - by Udo Rumpf (Added 8/27/99)
Landing Gear Issues - by Bob Kuykendall (Added 9/10/99)
HP-18 Landing Gear improvements - by Bruce Patton
RS-15 CG Hook Installation - by Doug Hoffman (Added 9/14/99)
HP parts in an Elfe PM3 - by Graham McLean (Added 9/22/99)
Folding Tail Fairing - by Tony Burton (Added 3/1/00)
Flap and Gear Actuation Systems - by Doug Hoffman (Added 10/18/03)
Pushbutton-Release Flap Crank - by Bob Kuykendall (Added 3/25/01)
Design to Improve Flap Handle Leg Clearance - by Bob Kuykendall (Added 12/19/09)
Crank Modification - by Udo Rumpf (Added 4/29/01)

Winglets, Airfoils, and Other Modifications

TEFLON Control Surface Gap Seals - by Wayne Paul (Added 11/15/08)
Wing Building - Udo Rumpf's design and building techniques (Updated 11/23/07)
Taping Hinge-lines - by Wayne Paul (Added 5/6/07)
An Airfoil for a 15 Meter Class Glider - by Udo Rumpf (Added 3/24/07)
HP-18 Airfoil Comparison Graphs - by Udo Rumpf (Added 3/24/07)
Udo Rumpf Airfoil - UDO 15.3 - by Udo Rumpf
Udo Rumpf Airfoil - UDO 15.3 Modified - by Udo Rumpf
Winglet Construction - Udo Rumpf's photo diary (Added 12/22/05)
Installing the Udo Airfoil on RS-15 N5724 - by Doug Hoffman (Added 8/29/05)

HP-16 Winglet Installation - by Brian Case (3/24/03)
Bending Wing Skins
for the RS-15, HP-16 and HP-18 by Airmate (7/5/99)
Spar Riveting Tool - by Bob Kuykendall (6/18/99)
HP-18 Taper Pins, Deck and Wing Root Modifications - by Udo Rumpf (2/3/99)
HP-18 Push Rod Attachments - by Udo Rumpf (Added 11/16/98)
Wing Modification and Re-profiling a 400 hour plus project - by Udo Rumpf (Updated 2/8/99)
Vacuum Assisted Wing Skin Bonding Technique RS-15, HP-16 and HP-18 (12/10/98)
Smoothing Wing Surfaces - by Richard Schreder (4/26/99)
HP-14 Wing Fence installation - by John de Jong (10/26/98)
Aileron/flap interconnect cam modification - by Terry Healy (9/2/98)
Winglet installation - by David Colling (Added12/16/97)
HP-16 Aileron/Flap modification - by Ron Leonard. (4/22/98)
HP-18 Aileron Roll Problem is Solved - by David Colling. (2/14/98)
HP-18 Aileron modification and HP-18 Additional Tips - by Bruce Patton. (Updated 12/19/97)
HP-18 Aileron Balsa Addition Instructions - by Bruce Patton (Added 11/7/05)
HP-18 and RS-15 Wing Spar Unriveting Tool - by Bob Kuykendall (Added 8/5/99)
RS-15, HP-16/18 Re-bonding Tips (Added 2/4/00)
FX-67 Turbulator Recommendations - by Udo Rumpf (Updated 9/4/01)
HP-18 Fuselage to Flap Seal - by Bruce Patton (Added 2/10/02)
HP-14 Flap and Aileron Construction - by Doug Hoffman - (Added 5/30/03)
RS-15 Wing tip Wheels - by Bill Hill - (Added 7/26/03)
Crude but Functional Wing-tip Wheels - by Wayne Paul - Updated 5/23/07)

David Colling has two HP-18s. One is currently flying and the other should be flying soon. He has a set of Masak HP-18 winglet molds. Winglets from these molds will fit (without modification) the HP-16, RS-15 and HP-18. The Region 10 handicap for David's HP-18 with winglets at 1.045. David's email address is (Updated 4/20/05)

Peter Masak's article "Winglet Design for Sailplanes" in Free Flight magazine, Vol. 2 1992, page 6 contains detailed information on his designs. The airfoils PSU-90-125 or RG15A-213 are preferred for the winglets. (Updated 1/27/01)

Ed Hollestelle also has a set of HP-18 winglet molds. He can be reached at Solaire Canada, 2371 Dundas St. E., London, Ontario N5V1R4 -- Phone (519) 461-1464. Email (Updated 3/27/02)

Udo Rumpf wrote an excellent article (Link updated 12/15/97) for Soaring Magazine, Oct, 1997 starting on page 27. His Super HP-18 project includes winglets, airfoil and fuselage modifications. The performance of the Super HP-18 is comparable to the ASW-20.


Canopy Crack Repair - by Mike Carris (2/27/09)
Canopy crack repair procedures - by Scott Correa. (6/10/99)
Super HP-18 Canopy Hinge System - by Udo Rumpf (11/2/99)
HP-18 Canopy Mechanism - by Hugh Gardner (10/21/99)
RS-15 Forward Hinged Canopy - by Bill Hills (10/19/06)
Thoughts on Canopy Hinge Design - by Bob Kuykendall (10/22/99)
HP-14 Canopy Replacement - by John De Jong (10/6/01)
SHP-18 Canopy Frame - by Udo Rumpf (5/10/00)
Window Vent Construction - by John De Jong (Updated 5/23/01)

HP Aircraft LLC/Aircraft Windshield- Canopies for HP-11, HP-14 and HP-18. Email:, Web site: These are quality canopies produced by Judy Gallo of Aircraft Windshield. Bob owns the tooling for the HP-11 and HP-14 canopies and has HP-18s canopies in stock. Judy owns the tool for HP-18 canopies. You many order HP-18 canopies directly from her. Phone: (562) 430-8108, Fax: (562) 598-0716 or mail to Aircraft Windshield Company, 10871 Kyle Street, Los Alamitos, CA 90720 . (Updated: 9/24/04)
Ray Poquette --Email: , Web page:, phone (916) 272-2556.

Instruments, Radios/Avionics, etc.

A Total-Energy/VHF Radio Antenna System -- by Les Sebald, Soaring June 1981. (6/19/98)
Wings and Wheels -- New and used item. Contact Tim Mara at (716) 664-6894 or via Email:
Cumulus Soaring Supplies - Flight Recorders, computers, software, cables, etc