Thinking about the OTL development of the P-38 the biggest change was from the earlier P-38 versions to the P-38J. This is the most visibly obvious change as the look of the front of the engines nacelles changes from the more streamlined shape to one more resembling the P-40s' nose.
Glacier Girl, a P-38F a provides a good view of the front of her engine nacelles.
And here is a later model, either a P-38J or L. Showing the change in the look of the nacelles.
These changes to the the P-38 were required to accommodate the more effective intercooler needed by the more powerful versions of the Allison engines with its new turbocharger. The old leading edge intercooler design wasn't adequate. The new chin location for the intercooler, packed in with the oil coolers worked but the wider shape did introduce more drag. I think a different approach to where to locate the oil coolers and prestone radiators could have been examined and developed in late 1942, early 1943. The new intercooler could still be able to fitted in about the same place in the nose.
Here are two pictures of P-51s showing their radiator housings from different angles. This helps
provide an idea of the width and length required for this installation. The P-51 radiator housing design
was able to utilize the Meredith effect.
Instead of the OTL changes the Lockheed engineers did for the P-38 I think a more advantageous though radical design change would see the fitting on a P-51 type radiator housing to each P-38 engine nacelle.
These would hold both the prestone coolers and the oil radiators. Pretty much a close copy of the P-51s' design in shape and size it would be able to use the Meredith effect as well reducing drag. The front of the engine nacelles would also be much slimmer thereby reducing drag. There would only be one opening needed for the intercooller intake slightly offset from lower centre of the front of the nacelle.
What about the main landing gear? Well, why does the placement of the radiator housing have to be directly under the centre of the underside of the nacelle same as the P-51? I think there is room to fit the housing on the lower inner side of each nacelle between the landing gear and the underside of the wing. Placed low enough to allow the flaps to be opened.
So try to visualize a P-51 style scoop and housing on the inner side of each engine nacelle starting about halfway back of wing chord. The benefits are the improved over all streamlining of the P-38 with the smaller nacelle frontal cross section, the removal of the draggy radiators from the tail booms and the advantage of using the Meredith effect. Also the weight of the oil coolers and radiators are moved closer the the planes' centre of gravity. And there is a reduction in piping for the prestone radiators. This all would require a larger redesign effort than the OTL changes but it would provide a better, faster airplane.
Perhaps while they are at this Lockheed can hasten the addition of the anti-compressibility tuck dive recovery flaps into this new production model. It will still need those too.
Glacier Girl, a P-38F a provides a good view of the front of her engine nacelles.
And here is a later model, either a P-38J or L. Showing the change in the look of the nacelles.
These changes to the the P-38 were required to accommodate the more effective intercooler needed by the more powerful versions of the Allison engines with its new turbocharger. The old leading edge intercooler design wasn't adequate. The new chin location for the intercooler, packed in with the oil coolers worked but the wider shape did introduce more drag. I think a different approach to where to locate the oil coolers and prestone radiators could have been examined and developed in late 1942, early 1943. The new intercooler could still be able to fitted in about the same place in the nose.
Here are two pictures of P-51s showing their radiator housings from different angles. This helps
provide an idea of the width and length required for this installation. The P-51 radiator housing design
was able to utilize the Meredith effect.
Instead of the OTL changes the Lockheed engineers did for the P-38 I think a more advantageous though radical design change would see the fitting on a P-51 type radiator housing to each P-38 engine nacelle.
These would hold both the prestone coolers and the oil radiators. Pretty much a close copy of the P-51s' design in shape and size it would be able to use the Meredith effect as well reducing drag. The front of the engine nacelles would also be much slimmer thereby reducing drag. There would only be one opening needed for the intercooller intake slightly offset from lower centre of the front of the nacelle.
What about the main landing gear? Well, why does the placement of the radiator housing have to be directly under the centre of the underside of the nacelle same as the P-51? I think there is room to fit the housing on the lower inner side of each nacelle between the landing gear and the underside of the wing. Placed low enough to allow the flaps to be opened.
So try to visualize a P-51 style scoop and housing on the inner side of each engine nacelle starting about halfway back of wing chord. The benefits are the improved over all streamlining of the P-38 with the smaller nacelle frontal cross section, the removal of the draggy radiators from the tail booms and the advantage of using the Meredith effect. Also the weight of the oil coolers and radiators are moved closer the the planes' centre of gravity. And there is a reduction in piping for the prestone radiators. This all would require a larger redesign effort than the OTL changes but it would provide a better, faster airplane.
Perhaps while they are at this Lockheed can hasten the addition of the anti-compressibility tuck dive recovery flaps into this new production model. It will still need those too.
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