wuzak
Captain
An earlier turboprop, the experimental XT-31
1980lb, 2300hp.
1980lb, 2300hp.
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Hello,
For years - I have pondered the reason for pusher type aircraft? Especially in the B36 configuration. Any thoughts?
what is your statement based on? The B-36 program had cost a lot of money and I think the men who made the decision knew what they are doing. The best aircraft engineers of that time were working on the pusher design and it is kind of strange when 70 years later someone criticize this without any proof.Stupidity, idiocy, insanity???? There are no gains here at all. Harder to make, harder to service, poorer lift on takeoff, poorer climb, worse stall, cooling issues (especially on an air cooled engine) and so on.
As for the cruising drag issue of a twin tractor it is just down to careful engine nacelle/wing design (near the engine of course), do that then it becomes a non issue.
Bit like the Do-335, a tribute to monomania about a single issue and showed a complete lack of creativity.
Not even sure this even a solution for more economical high speed cruising at high altitudes, as you will need a bigger wing for the lift (=more drag) and/or a higher angle of attack (=more drag).
Write this off as a dud..... Brewster Buffalo or Defiant stuff. Sort of like the ideas we all get after a few too many drinks and get all excited about ... then write off in the cold light of the day (after the hangover had gone).
what is your statement based on? The B-36 program had cost a lot of money and I think the men who made the decision knew what they are doing. The best aircraft engineers of that time were working on the pusher design and it is kind of strange when 70 years later someone criticize this without any proof.
cimmex
what is your statement based on? The B-36 program had cost a lot of money and I think the men who made the decision knew what they are doing. The best aircraft engineers of that time were working on the pusher design and it is kind of strange when 70 years later someone criticize this without any proof.
cimmex
until the B-52 it was the Only bomber the US had which could strike Moscow with a Thermonuclear weapon in 1950, multiple nuclear weapons in 1947.
In June 1948, Convair delivered the first operational B-36A to SAC's 7th Bomb Group at Carswell Air Force Base, across the runway from its Fort Worth plant. Big as the B-29 Superfort was, it could nearly fit beneath one wing of a B-36. Despite the difference in size, the two airplanes had similar vertical tails, and they had slim fuselages, like cigarettes, round in cross-section, with two pressurized crew cabins separated by two bomb bays and connected by a tunnel.
But the wings were different. The Superfort's were thin, straight, and glider-like, while the B-36's wings were more than seven feet thick at the root, enough for a crewman to crawl in and reach the engines or the landing gear in flight. The wings were tapered, with the leading edges swept back, and the effect of that, combined with the wings' location so far back on the fuselage, made the airplane appear out of balance. Strangest of all, the B-36's six Pratt Whitney Wasp Major engines were faired into the trailing edges, with the propellers located aft in the pusher configuration. Although it was supposed to reduce the propeller swirl's turbulence over the wing, the pusher design was rarely used on U.S. aircraft. Apparently it worked, though, because the B-36 had very low drag. The main drawback was that air for cooling the engines was ducted from intakes in the leading edge of the wing, and there was never enough of it, especially at high altitude.
The propellers were 19 feet in diameter, and to keep the tips from going supersonic they were geared to turn less than half as fast as the engines. The engines and propellers produced an unforgettable throbbing sound when the B-36 flew overhead. A friend of mine remembers the sound from his boyhood as a "captivating drone. The noise went down to your heels, it was so resonant. It just stopped you in your tracks. You looked up into the sky to try to find this thing, and it was just a tiny cross, it was so high." Others remember that it rattled windows on the ground from 40,000 feet.
The propellers were reversible for braking on landing, but sometimes they reversed in flight or while the airplane was straining to take off--at least once with fatal consequences. The stainless steel firewalls enclosing the engines cracked. The cylinders overheated. Lead in the gasoline fouled the spark plugs at cruising speed. Each airplane had 336 spark plugs, and after a flight lasting a day and a half, a mechanic would have to haul a bucket of replacement plugs to the airplane to service all six engines. The engines leaked oil, and sometimes a flight engineer had to shut one down because it had exhausted its allotment of 150 gallons.
Then there was the "wet wing." The outboard fuel tanks were formed by the wing panels and sealed at the junctions, and after the wing flexed for a few hundred hours the sealant was apt to fail. Jim Little recalls that one airplane leaked so badly "the ground underneath was just purple [from the dye in the high-octane gasoline]--it was raining fuel under that airplane."
Pilot opinion of the B-36 tended to run to the extremes, but most crew members loved it--"this big, wonderful old bird," Jim Edmundson calls it. As a colonel in the early 1950s, Edmundson commanded a B-36 group at Fairchild Air Force Base near Spokane, Washington. But even he admitted that the airplane could be a chore for its pilot--"like sitting on your front porch and flying your house around."
Of course most of the pilots were young and eager, and the older men had flown worse contraptions during the war. "It was a noisy airplane; it was big," former radioman/gunner Raleigh Watson recalled at a B-36 reunion at the Castle Air Museum in Atwater, California last September, "but it was comfortable, and I think we felt it was a safe airplane, a very well-built airplane." Moxie Shirley, a pilot with more than a thousand hours in the B-36, loved the airplane, declaring that it "kept the Russians off our backs." But he went on to add, "Every crew that ever flew that airplane had stories that would make your hair stand on end."
Altogether, 1951 was a good year for mega-bombers. Margaret Bourke-White rhapsodized over the B-36 in a photo-essay for Life magazine, with photographs taken at 41,000 feet, where the sky "was a color such as I've never seen, the darkest blue imaginable, yet luminous like the hottest cobalt, too brilliant for the eyes to bear." She photographed fluffy white contrails streaming from the reciprocating engines, a 55-foot scaffold used to repair the rudder, and (from both ends) the marvelous flying boom that refueled bombers in flight
B-36 crews speak of 45-hour missions, presumably with fuel cells instead of nukes in the rear bomb bays; at cruise speed, a "featherweight" could travel almost 9,000 miles in that period. The official ceiling was 41,300 feet, but again, crews say that they routinely flew higher than 50,000 feet, and one man--John McCoy, quoted in Thundering Peacemaker--boasted of soaring to 58,000 feet. On missions over China, McCoy said, his RB-36 was chased by MiG fighters that couldn't climb anywhere near it. U.S. fighter pilots of that period also recall B-36s cruising comfortably well above their own maximum altitude. Not until the advent of the "century series" fighters--the F-100 and up--would the B-36 be challenged. Whether the RB-36 ever overflew Russia is anyone's guess, but it was the U.S. altitude and distance champ until the Lockheed U-2 came on line toward the end of the decade.