I have owned multiple Pilatus P3s since early 1990 and have over 800 hours in the stock P-3.
This aircraft is a good handling, sturdy and reliable aircraft with one shortcoming; its lack of power to be competitive with its updated classmates.
I purchased a P3 airframe a couple of years ago with a goal to address the power issue and to modernize the avionics and systems. I learned in the mid 90s of a California based P-3 that had been upgraded with a Lycoming IGSO-540 380 HP engine. After inspecting and flying the aircraft, I concluded this installation, with its supercharger and related maintenance issues, was to complex for me.
I wanted a normally aspirated engine with the most power, without any aftermarket improvements or modifications. I choose the Lycoming IGO-540 with 350 HP. This engine was used only in some Aero Commander Twins.
This engine fit into the original motor mount without modifications. A new oil sump and
intake plenum was necessary to clear the nose gear actuator.
The Engine is 1 ½ in wider than the original which required some internal modifications to
the cowling. We created a new nose bowl to optimize cooling and reduce drag.
We used Airflow Performance’s fuel injection system, mounted a large oil cooler below the engine and fabricated a new air inlet. This keeps oil temps in the green and adds 2-3 inches of manifold pressure at high cruise.
The airframe was stripped of all the old avionics and military parts, as well as wires and systems.(approx. 160lb)
We fabricated new front and rear instrument panels. The fuel gage, flap indicator
and G-Meter was the only original instruments used. A vacuum system was installed to
operate the horizon front and rear, HSI in front and DG in rear. The airspeed, turn and bank, VSI, altimeter were replaced with new instruments.
New engine gages were installed consisting of: tachometer, manifold gage, JPI engine analyzer, fuel flow/PSI, digital oil temp/PSI with alarms, amp/ vac PSI gage. A 20 gallon auxiliary fuel tank was installed bringing the total fuel to 62 gallons.
Hermann H (owner of the first rebuild) and I collaborated on the engineering and rebuilding of our P3s. Where mine is a work in progress, Hermann is enjoying many trouble free hours of flying his since completion.
Jerry Jeffers (P-3 Owner) of Air Associates, Inc. engineered and installed a two axis Autopilot
System, as well as supplied and installed a Garmin 430, Garmin Transponder, Intercom/Audio Panel , and Becker Com Radio in the first rebuild.
Performance Observed
Climb
800 MSL 60*F 1500 fpm
Cruise Climb thru 3000 ft 28in MP,2700RPM, 130 KIAS, 1200 fpm
Cruise
5000Ft
22in MP, 2700 RPM, 16.0 gph, 165 KTAS
24in MP, 2700 RPM, 18.0 gph, 174 KTAS
26in MP, 2700 RPM, 20.7 gph, 180 KTAS
26in MP, 2900 RPM, 22.5 gph, 185 KTAS
7000Ft
20in MP, 2700 RPM, 14.4 gph, 162 KTAS
22in MP, 2700 RPM, 16.5 gph, 171 KTAS
24in MP, 2700 RPM, 18.3 gph, 177 KTAS