Osprey GP-4

  • Osprey GP-4
  • Osprey GP-4
  • Osprey GP-4
  • Osprey GP-4
  • Osprey GP-4

Aircraft Specifications

Aircraft Description

New and 99% Completed  •  Aerobatic Aircraft

Prized Build: Only $74,900!

As Progress is Made for Airworthiness Certificate, the Price will Increase!

Located in Las Cruces, New Mexico

Two Jacks & Engine Lift Included with Sale

All Literature, Logs, & Inspection Records Included with Sale

Osprey GP-4 Video


Original kits as called out on blueprint - Wicks Aircraft - $10,855
Welded assemblies by Darry Capps - $8,000
Engine, new from factory IO-390 - $33,765

Dynon EMS D120 - $2,200
Dynon EFIS D100 - $2,450
Dynon HS 34 - $650
Dynon Emission Kit L4F - $862
Val's Navigation INS 422 - $1,750
XCOM - $394
Air Speed 30-300 - $378
VSI 2000 ft/min - $531
ALT - $1040
Compass - $216

Engine Cowling - $2,600
New Hartzell Constant Speed Prop Designed for GP-4 - $13,250
Odyssey Battery - $210
Seats Upholstered - $555
Canopy & Windshield - $1,500
Strobe Lights - $887
Blueprints - $385
Parts from Aircraft Spruce since 2008 - $13,900

Total: $96,378


New Lycoming IO-390 A1A


New Hartzell Constant Speed Prop that is Specially Designed for the GP-4


Ready for Paint

Additional Information

Work Left To Be Done:

  • Weight & Balance
  • Install panel under cockpit. To be left off until after first flight. When panel is installed, two actuators have to be installed.  All parts are there to complete the installation.  These actuators close the inner door to the main gear.
  • Install actuators on panel under seats.  Actuators close main gear inner door.  All parts are in drawer.
  • Nose door to be installed and nose gear linkage to be hooked up to rest of gear retract system.  Door made ready to install.  All parts in drawer.  Linkage for nose door closure may or may not need to an adjustment.
  • Paint and aircraft identification.
  • Engine cowling could be worked for a better fit at Constant Speed prop.
  • All work performed to the bluprint and to .010 and .030 tolerance.

Tail number registered with FAA - N138GP.

I have most receipts to verify what I have into the aircraft - $96,378.  Most of it is for the brand new 390 engine and the Constant Speed prop.

Aircraft is portable on an auto trailer with a height above asphalt to top of tail will be about 13' 5".  This will clear all interstate highway overpasses ending in 0 and 5.  Wings in line with highway and tail having no overhang on the sides.

I have everything to complete the aircraft and it all goes with the aircraft.

I had advisors to my home for firewall forward, as that is not in my expertise.  They advised me to cover all fuel and oil lines to protect them to 500 degrees Fahrenheit and seal the ends with a special tape.  They also advised to remove plastic tywrap from the engine mount as they will wear out the steal.  I put hose around the engine mount and placed the tywraps around the hose.  On a return visit for a final inspection, I was told the engine is equivalent to a factory installed engine.

Articles in homebuilt magazine about all the bad stuff causing accidents.  Not THIS aircraft.  The blueprint is above standard and easy to read with a lot of detail.  This aircraft is to blueprint.  No reversed controls or missing cotter pins.  This is a safe aircraft.  I am now 83 years old and cannot pass my physical.  I am hoping whomever buys it invites me up once and let me see what it is like to fly at 275 mph, which is the speed that George Pereira estimated my aircraft will fly at!

After saying all this about quality, I have to say the tires are new, but old.  I used to own a Beech Debonair which tops out at 150 mph.  The GP-4 will pass it at 275+.  Imagine you standing and watching a car pass you at 125 mph.  George Pereira passed a Debonair at 240 mph in California along with another GP-4 with him flying in formation.  I do not know exactly what the GP-4 will top out at.  The designer advertises 240 mph and claims speeds of 250 mph.  I have a brand new IO-390 Lycoming which has 10 more HP and it is an advanced engine.

This aircraft is 100 percent to the blueprint and the mil specs.

All my measurements are to +/- .030 to the best of my ability.

All hardware is grade 8.

ELT is old frequency.  New one is same shape and size.  Just remove and replace.  Possible some credit for old unit.

35 years experience as inspector on the floor inspecting aircraft and satellites, supervisor over same inspectors I worked with.  Became quality assurance engineer at Lockheed.  I have in excess of $96,000 in parts and materials that can be verified with Aircraft Spruce.  Any hardware I have will go with the aircraft.  And there is a lot of that.  Aluminum, steel, copper and what have you will go with the aircraft.  Also, a lot of nuts, bolts, and lots of material.  The GP is transportable on a long auto trailer with the nose gear retracted and tail in the air with no overhang on the sides.  The tail will be 13' 5" off the pavement and can travel US highways ending in 0 or 5 with sufficient clearance.

I am currently trying to get someone to do the ground checkout and the flight airworthiness of the GP-4.  As it is now, I am willing to take a beating on the selling price.  As I progress with the airworthiness certificate, I will have the aircraft painted red as most of the GP-4's are.  The further I progress, the more the price will be.  A buyer could save quite a bit by buying now.  The GP-4 is presently in my garage, but can be easily transported to the aircraft with no problem.

About The Builder
34 years in aircraft and satellite business.  I know mil specs.  Worked at Lockheed Missiles and Space Company as inspector on the floor, then to supervisor of those I worked with, then to quality engineer and material review board.  Can read any blueprint put before me.  Worked to close tolerances of .030 +/- .010.

Additional Aircraft Info.

Serial Number 138GP
Registration Number N138GP

Seller Information

Ralph Cristofaro
(575) 526-7722
(408) 891-2675
Las Cruces, NM
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