Regarding the supposed high wing loading of the Martin B-26.
All of the following is from The Martin B-26 Marauder by J.K. Havener. Most of the historical info is from the archives of the Martin-Marietta Corp.
The B-26 was ordered into production before the prototype had finished testing and so improvements and fixes developed by test were incorporated on the fly. In the transition training for the plane the accident rate was quite high leading to an inquiry as to whether or not the project should continue.
That it did continue was largely a result of the actions of two people, then Col. Jimmy Doolittle and Capt. Vincent (Squeek) Burnett. Doolittle had the opportunity to fly one and was impressed by its handling and performance. When the plane ran into trouble he was called in to investigate the feasibility of continuing with the production and introduction of the B-26 into operational use. Doolittle immediately thought of Burnett to do the actual investigation of the difficulties and to develop a plan to overcome them.
Doolittle and Burnett had met during barnstorming and racing days in the 1930’s. Everyone knows Doolittle’s accomplishments but Burnett is unknown. Here are a couple of Burnett’s flying feats. Here is a photo ofhim and his TravelAir biplane making a low pass at Miami in 1940. (Photo by Miami Herald via Evelyn Burnett)
And during the bad time for the B-26 the word was that it was absolutely fatal to turn into the dead engine during single-engine operation. Burnett embarked on a flying demonstration at various places to show that the plane was as safe as any plane could be when properly handled. For example here he is shown circling the tower at Omaha airport at 50 ft. and turning into the dead engine. (Photo Glen L. Martin Co. and Evelyn Burnett)
In the investigation Burnett found that: The Curtis Electric propellors, a new design, had a habit of running away. Curtis was put on notice to fix it and they did.
The nose-wheel strut had the bad habit of collapsing on landing. Martin strengthened it.
The instructors were themselves ill-trained in the plane. Many of them were just out of flight school and had been rushed through an instructor training routine.
The mechanics were also not well trained in maintaining the plane.
Martin and Burnett developed an instructor training program to bring the instructor skills up to snuff and Martin brought mechanics to their factory for intensive maintenance training and practice.
In addition, Martin put bigger engines on (2000 HP vs. the original 1850) and lengthened the wing from 65 to 71 ft.
As a result of the rescue program the army learned how to maintain and fly the airplane and it became one of the safest with the lowest combat loss rate of any US bomber.
Now the twist is this. The original 65 ft. wing had a total area of 602 sq. ft. and the plane max weight was 27720 lb. This gives a wing loading of 46 lb/sq. ft.
After the wing was lengthened to 71 ft (area 658 sq. ft.) in order to reduce the loading, the army then ordered changes in armor, armament, and bomb load that increased the max weight to 37000 lb. for a wing loading of 56.23 lb/sq. ft.
And after the dust had all settled it turned out that the Douglas A-20 and the Lockheed P-38 both had a higher training accident rate than did the B-26.
How 'bout that.