A Heinkel He 177 with its crew, Sept. 23, 1944. Heinkel finally gave up on the twinned DB 606 engines and redesigned the He 177B to have four conventional engines, with three prototypes flying in 1944, but by then it was too late, with bomber projects being cancelled and production concentrating on fighters.
(Bundes archive photo)
Put yourself in the shoes of a German pilot during World War II. It’d be more than just a bit concerning if your assignment was to fly the “Flaming Coffin,” a.k.a. the “One Way Bomber” or “Volcano.”
But the hot, flammable He 177 Greif, or Griffin, was Nazi Germany’s only long-range heavy bomber produced in appreciable numbers. The 35-ton machine — when fully loaded — was a mistake, and more importantly, contributed to the German defeat by sucking up valuable resources into an ineffective and compromised aircraft.
The all-metal He 177 was both interesting from an engineering standpoint and fundamentally flawed for the same reason. In 1937, soon after manufacturer Heinkel Flugzeugwerke delivered its first prototype, the military ordered the company to modify the Greif into also being capable of dive bombing, a tactical focus bordering on obsession within the Luftwaffe.
Yes, dive bombing in a heavy bomber.
Except dive bombers tended to be on the smaller size given the intense stress and high Gs caused by pulling up after a dive. Because of the stress, dive bombers such as the Ju-87 Stuka needed to be tough and therefore heavy.
But not too heavy, and not too big.
The He 177 was too heavy and too big, however, and could not do a proper, near-vertical dive without plunging into the ground. It could do a shallower dive, or glide, but not very well.
Light aircraft such as fighters could dive-bomb, too, but this was extremely risky as they could dive too fast to pull up in time, or risk breaking up during the descent. And dive bombers needed to get close to be accurate.
Air brakes, of course, could slow a dive. But balancing size, weight and sturdiness was always key factor in determining a dive bomber’s success.
Another obvious problem for the He 177 was the aircraft’s size, which made it an easy target from the ground. A payload of more than 13,000 pounds of bombs and a range of more than 3,000 miles means it guzzled fuel, and Heinkel kept adding on weight to strengthen the Greif’s structure.
So as the plane “improved,” it became even thirstier for fuel … just as Allied bombers began devastating Germany’s oil supplies. A constellation of machine guns rounded out the He 177, but the precise configuration of its defensive armament changed over time.
“I had to ground that aircraft because it consumed too much gasoline, and we just didn’t have enough of it,” Luftwaffe chief Hermann Goering told the U.S. Strategic Bombing Survey after the war.
The Greif was compromised from almost the very beginning. What’s curious is how Heinkel tried to solve the inevitable engineering challenges that derived from the dive-bombing requirement.
Heinkel gave the He 177 four DB 601 engines interconnected in two pairs, with each pair responsible for powering a single propeller. Each pair also produced more than 1,900 kilowatts of power each, and the two propellers — as opposed to four in most heavy bombers — gave the plane stability during a gliding descent, although it obviously couldn’t dive as steep as a Stuka.
As a result, the Greif was technically a glide bomber, not a dive bomber.
Regardless, it was still way too big and terrible at the job. More seriously, the engines were prone to bursting into flames. The engines were complex, fitted extremely tightly — and covered in a similarly tight cowling — that made them run hot and hard to maintain.
Excessive heat and risk of fire was a constant concern.
The He 177 even had a negative effect on other experimental German weapons. The Nazis developed two high-tech anti-ship guided bombs, the liquid-fueled Hs 293 and the free falling Fritz X.
Both bombs were radio guided and the He 177 served as their primary delivery platform. But the He 177’s poor performance “greatly limited the bombs’ employment, indicating Germany’s integration problems,” U.S. Air Force Lt. Col. Todd Schollars wrote in the Air Force Journal of Logistics.
The negative consequences of the He 177 reached beyond bombs to more radical and experimental planes. The Messerschmitt Me 262, the world’s first operational jet fighter, came too late in the war to make a major impact — and it would’ve been unlikely to change Germany’s fortunes had it arrived sooner. But the bad experience of the He 177 contributed to Adolf Hitler’s skepticism about the new jet fighter.
Hitler steered precious resources into the Me 209 — a planned successor to the Bf 109 fighter plane — knowing it would cut into the Me 262’s production, according to Lt. Col. Schollars.
Finally, Germany built more than 1,000 He 177s. Remember, each bomber had four DB 601 or DB 605 engines — the latter an upgrade to stop the fire hazard.
They were the same engines used in the Bf 109.
That was a lot of engines built for the largely useless He 177, and the Luftwaffe could have fought longer and harder, and with more Bf 109s, had it not been so seduced by dive bombing — which lost its tactical effectiveness once the Allies gained air superiority.
Richard Suchenwirth, author of the 1959 book Historical Turning Points in the German Air Force War Effort, partly blamed the He 177 for ending the Luftwaffe as a war-capable entity.
He also referenced a proposed version of the Greif with four propellers:
In the report of a fighter staff conference which took place on 3 July 1944, the following appears:
“… In a conference lasting nearly five hours with the Reichsmarschall on Saturday, we were told that the old He-177 will be pulled out of production as soon as those few machines now being finished are out of the way, and that the entire labor force concerned will be freed for our use in other programs. Moreover, it was decided not to start production on the new He-177, not even in limited numbers. This means that the entire working plant — labor force, equipment, and everything else — is at our disposal.”
A little more than ten months later, Germany’s ruin was complete. It is certain that the tragedy of the He-177 was one of the factors which had contributed to its downfall.
There’s an important lesson there. Over-investing resources in a bad design can help destroy your air force.
(Robert Beckhusen - The Buzz / The National Interest)
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