Thanks for posting that.

My old Twin Beech mentor was a ferry pilot that flew most of the WWII multiengine aircraft.
It wasn't until I had flown most of them too and a Link trainer that I appreciated his description of the B-24. He said that it flew like an over grossed Link trainer.

This is also a good read about the Davis airfoil from Wikipedia:

The Davis wing is a World War II-era aircraft wing design that was used by Consolidated Aircraft on the Consolidated B-24 Liberator, as well as other models. The airfoil had a lower drag coefficient than most contemporary designs, which allowed higher speeds and created lift at relatively low angles of attack. Its use in designs ended almost immediately after World War II.

Development and use
Theory and testing
In the summer of 1937, Reuben H. Fleet, president of Consolidated Aircraft met with David R. Davis, a freelance aeronautical engineer who was seeking funds to develop his airfoil design, the "Fluid Foil".[citation needed] Davis had designed the profile "in reverse", starting with a basic low-drag teardrop shape and then modifying it to provide lift. In comparison with conventional designs, Davis's design was relatively thick, having a short chord while still being deep enough to allow a high aspect ratio. Davis claimed the new wing would offer reduced drag over designs then in use, and would offer considerable lift even at a small angle of attack. The thick wing would also provided space for fuel storage, or even embedding engines, an idea that was in vogue at the time.

He approached Consolidated to license it for their large flying boats. The ability to generate lift at low angles of attack made it particularly attractive for flying boats because it would reduce the need to pull up the nose for takeoff and landing, which was limited in flying boats by the surface of the water. Neither Fleet nor Isaac M. Laddon, Consolidated's chief engineer, were impressed and Davis failed to convince them to try out his new design.

A few days later, however, Laddon changed his mind and convinced Fleet to pay for construction of a model and wing wind tunnel test at the California Institute of Technology. They intended to compare the design to one that had been designed in-house. Initial results of the Caltech wind tunnel tests were disappointing. Test instruments did not support Davis' predictions. However, Davis and others determined that the Caltech wind tunnel's instruments were not sufficiently sensitive to detect improvements from the Davis wing tests, despite being among the most sophisticated of their kind at the time. After re-calibration of the Caltech wind tunnel instruments, tests showed significantly improved readings.[1]

The results of the wind tunnel test were so good that the engineers were skeptical. Caltech recalibrated its wind tunnel and ran them a second time, and then a third time. When it delivered its report to Consolidated it indicated that the wing appeared to deliver everything it claimed, but Caltech also suggested it might be a wind tunnel fluke, something that gives good results only in the tunnel. This is a common problem since the tunnel's walls affect the results by increasing the effective aspect ratio, or the Reynolds number used could have been incorrect.

Real world use

A B-32 Dominator in flight
Fleet allowed it to be used on Consolidated's new twin engine flying boat, the Model 31 XP4Y Corregidor. The Model 31 made its first flight on 5 May 1939, vindicating the Davis wing. By this point Consolidated was already working on a secret project for a new bomber to improve on the Boeing B-17 Flying Fortress that was just entering service, and had selected the Davis wing for this project as well. The Model 32, which would become the B-24 Liberator, first flew on 29 December 1939. The same basic wing would also be selected for the Consolidated B-32 Dominator. However, the wing was thinner than on the B-17 Flying Fortress and many Consolidated B-24 Liberator units suffered heavily, as wings would often give out and snap off when hit by gunfire. Because the wing was so high, a tricycle landing gear was used, though it made ditching the plane harder and complicated belly landings.

Limitations and abandonment
Only later was the reason for the Davis wing's performance properly understood. Largely through accident, the shape maintained laminar flow further back from its leading edge, to about 20 or 30% of chord compared to the 5 to 20% managed by most airfoil sections of the era. Although later designs greatly improved on this, with some maintaining laminar flow to upwards of 60% of chord, the Davis wing represented a great improvement at the time.

The thick profile of the wing quickly led to its being superseded. Although aerodynamic tests prior to the war had demonstrated that high-speed drag was strongly associated with thick wing profiles due to wave drag, it was only late in the war that higher speeds made that an insoluble problem. As speeds of aircraft increased, the Davis wing's reduced low-speed drag could not compensate for its increased high-speed drag.

Author Ernest Gann complains that one of the cargo planes he flew "couldn't carry enough ice to chill a highball". Was this the Davis Wing?

Am I the only one who can't stand Ai voice overs with so many mistakes?

The same.

“It was said that the collection of parts known collectively as the “C-87” would never replace the airplane.”

“It was a ground-loving bitch, and with heavy loads it rolled, snorted, and porpoised interminably before asserting its questionable right to fly.”

That video had a smattering of facts sprinkled across a whole lot of wrong/inaccurate/out of context information.

Flying the Davis airfoil has a few surprises. Hand flying perfectly trimmed in smooth air it will fly along for a while and without any warning it will either began to pitch up or down. When retrimmed it will fly along for a while and do it again. I suppose if there was a working autopilot it would handle this, but the flying examples today are "sans George".

There is also a warning not to exceed 115 knots with full flaps. If you do it the airplane will really surprise you when it pitches over abruptly taking a very large amount of nose up elevator input and a reduction of airspeed to regain control. I was once on a training flight with several prospective new copilots doing landings. I had made it a point to stress this situation. A retired Delta captain was in the right seat turning base to final getting slightly high. He starting pitching the nose down to correct and the airspeed started to increase. In a 30 degree bank close to the ground the nose suddenly pitched down and I had to take the aircraft. He didn't want to fly the airplane anymore after that.

Th rudder pedals are also a unique design. They look like the foot measuring devise at a shoe store and slide horizontally in the floor with the tops activating the toe brakes. Since the airplane has no nosewheel steering, grabby brakes without antiskid and is short coupled it is quite difficult to control smoothly on the ground, If you need brake on one side someone has to hold the opposite side rudder pedal from moving when applying brake pressure. The typical procedure is to have the pilot not flying "block the rudders" on landing roll out when the rudders loose effectiveness.

If you have never flown some of these old airplanes you really don't know how good we have it these days with boosted controls, nosewheel steering, antiskid, reverse, air conditioning, stall warnings, stick shakers, stick pushers, auto pilots, etc.

Tell us more …

Thanks Charles. Was that the CAF Diamond Lil you were flying?

If so how would that compare to the later nose turret equipped B-24s?

The B-29 is pretty high aspect ratio. How do the airfoils compare to the B-24?

A lot of what we hear about B-17s vs. B-24s turns out to be wrong

I had a patient who was a B24 pilot. He said the B24s were called "whistling s**thouses" for the sound they made with the bomb bay doors open. He told me "one a day in Tampa Bay" referring to training accidents.

One a day in Tampa Bay was a B-26 thing.

One a day in Tampa Bay was a B-26 thing.

The airplane had no VMC or blue line numbers published. So it would VMC and crash. After they studied this and applied that information into the training, that stopped.

It appears that the best SE rate of climb is 170 miles an hour, that plane also had short wings. It was built for speed, and airspeed is life.

My FIL flew both of them. He LOVED the B-29. He hated the B-24.