This month the work on the control surfaces continues. The turbosupercharger system ducting is also progressing nicely. Two exciting milestones were reached in October as the landing gear were mounted in the wings and an R-2800 was affixed to the engine mount for firewall forward mock up work.
In the history section, we look into the long range challenges a pilot had to endure on missions lasting as much as 8 hours in a tropical climate.
Work on the rudder, flaps, and aileron linkage was a big part of the restoration work this month.
The main landing gear assemblies require a great deal of precision fitting to be sure they will function flawlessly. They were fitted, adjusted and installed in October.
One of this month’s milestones was the trial installation of an engine for mock up purposes. This allows all the connecting assemblies to be fitted in readiness for the delivery of the airworthy overhauled R-2800 when it arrives.
July of 1944 was a relatively quiet period for the 35th Fighter Group. The 39th Fighter Squadron flew no combat missions between late June and the beginning of August. The lull in combat allowed for experimentation in the long range operation of the new P-47-23s. Training in the new techniques discovered as a result of these experiments, took up much of July.
Flying from Nadzab on August 7, 1944, Major Richard Cella led a flight of twenty-six of the new P-47D-23s on a 900 mile mission to Noemfoor. The task of the mission was to cover the building of airfields on Middleburg Island. Similar missions continued for 6 weeks, but the 39th was able to move up to Noemfoor earlier than that.
The 39th conducted its first operations from Noemfoor on August 9th. Noemfoor offered some significant advantages with its 7000 foot compacted coral runway. Continued testing of maximum takeoff loads could be conducted on the long, smooth, and relatively unobstructed, coral runway. The squadron settled on two 175 gallon tanks under the wings and an additional 75 gallon belly tank. The combined total of these three tanks was 425 gallons of fuel, which added 2,550 lbs. to the takeoff weight. With this additional weight, the minimum take off speed was found to be 125-130 mph. That is 15 to 20 mph higher than the Thunderbolt without the drop tanks.
During this time period, Charles A. Lindbergh visited various 5th AF and Navy fighter groups as a consultant. His role was to help improve range and load carrying performance of the fighters in use in the SW Pacific theater.
Lindbergh visited the 35th Fighter Group on August 14, 1944 and presented his increased range procedures.1
The famous aviator demonstrated that by raising manifold pressure and lowering engine revolutions, fuel economy was greatly improved in the P-47.
On August 20th, another long range mission went on a fighter sweep led by Captain Gordon Prentice. The duration of that mission was over 5 hours and 20 minutes, making it the longest mission the 39th Fighter Squadron had flown, and perhaps the longest of any 5th AF mission to date.2
1 Charles A. Lindbergh, The Wartime Journals of Charles A. Lindbergh, Harcouirt, Brace, Jovanovoch, Incv., New York, New York, 1970,p 905-906
2 John Stanaway, Cobra in the Clouds,Historical Aviation Album 1982.
With the maximum range techniques Colonel Charles A. Lindbergh encouraged, together with the knowledge learned from the experiments that the squadron pilots conducted, the P-47 could now range out over nearly triple the range experienced before these innovations.
“No longer would the skeptics berate the P-47’s range. Later in the year, the squadron registered missions up to eight hours.”3
These techniques certainly increased the combat utility of the Thunderbolt in the SW Pacific, but what is seldom discussed is what a price the pilots paid on these extended missions.
To take advantage of the technique of high manifold pressure and low rpms, the long range flights had to be flown at low altitudes. High enough manifold pressure couldn’t be maintained at the low rpms if the P-47s flew much higher than 3,000 feet.
The pilot of a P-47 sits just above two tubes that supply hot exhaust gases to drive the turbosupercharger and behind the big radial R-2800. A great deal of heat is generated by the powerplant and turbosupercharger system. Even in a tropical environment like New Guinea where triple digit temperatures on the ground were common, pilots would normally mitigate the heat to some degree by climbing to an altitude that was cooler. Unfortunately for them however, the new long range techniques didn’t allow that, so pilots sweated in their cockpit for as long as 8 ½ hours. The pilots would return dangerously dehydrated, and completely exhausted from missions like these.
3 John Stanaway, Cobra in the Clouds, Historical Aviation Album 1982, Temple City, CA, p.29