A B-17 Story (part 5)

1000 B-17 and B-24 bombers stretched end to end, adds up to 189 miles. If they are 3 abreast nose to tail, that is 63 miles. By July 1944, the 8th Air Force had tried several styles of “Combat boxes,” and final settled on the 27 plane combat box. These flying formations would stage aircraft at different flight levels allowing for station keeping or distance between aircraft. A bomber formation could be as high as 30,000 feet and staged vertical for a mile. In some cases, a bomber formation would be stacked vertically from 20,000 feet to 30,000 feet and 200 miles long.

There were dozens and dozens of airfields in England. Unlike today where an airfield is paved and can support an 850,000 pound aircraft, bomber and fighter fields in England were in many cases grass fields. This is where “Airfield” comes from.

By Mid 1944, a bomber groups may have had 50 aircraft or more. To generate a 1000 bomber formation would take 20 Bomb groups working in concert.The B-17 can cruise at 180 MPH. The climb rate loaded is 900 feet per minute. Climb speed is different than cruise speed. The higher the rate of climb, the slower the aircraft would fly. If the aircraft climbed out at 100 mph, it would travel a horizontal distance of about 2 miles for every 1000 feet of vertical distance. Climbing to 30,000 feet would take at least 30 minutes if not longer and cover 60 to 75 miles. The bomber groups would try to be at over 20,000 feet by the time they crossed the English Channel and entered the combat zone.

The timing of the B-17 launches was crucial. England had over 100 airfields within a small area. 50 aircraft would take off from one airfield followed by 50 more from another airfield only a few miles away, followed by 50 more and so on. By the time the first cell of 50 B-17s climbed to 18,000 feet and cleared the English channel, there were still B-17s and B-24s taking off. It was crucial that every 27 aircraft combat box be in flying formation by the French coastline if not sooner.

The stacking of aircraft was also important. The first cell would be lower and the next would be higher and so on. This way, one B-17 does not drop its payload on a trailing aircraft. The bombers would maintain this style of flying formation until the “Bomb run.” Then, all aircraft that will bomb a specific location would have to tighten up the formation in order to drop on target. This is where the bombers were the most vulnerable. This is where the FLAK gunners could set their 88s and 128mm guns at one point and fire away. The FLAK gunners had much better chance at downing a B-17 during the bomb run, especially when 100 aircraft are in a tight formation in order to bombs a rail head or factory etc….In order for a cell of  aircraft to hit the bomb target from 20,000 to 30,000 feet, the bombs would have to drop from every aircraft at the same point in space. Once the lead aircraft stated “bombs away,” over the aircraft bombing cell frequency, it was up to the Bombardier and his Norden Bomb site to hit their target.

Of course the mission planners sought to mix up the bombing schedule and altitudes to avoid the obvious, but the FLAK spotter logged all the gun coordinates, and knew what was being bombed and from what point within minutes. The FLAK spotter knew at what a altitude a bomber was flying by size recognition and radar. It wasn’t long before the trailing aircraft were getting slaughtered.

The British avoided all this by flying at night.

In Berlin for instance, there was a huge complex of FLAK towers that could sustain 8000 rounds of fire a minute. Even if only a 1/4 of the guns were trained on bombers targeting the Berlin marshaling yards, this meant 2000 rounds every minute at one point in space. While the vertical stacking was effective in minimizing losses, a trained FLAK gun spotter and a trained gun crew could change fuse altitudes very very quickly. These realities played hell on bomber crews.The winds aloft in some respects was the only variable. When the aircraft encountered a head wind, a tail wind or a side wind, it affected the bomb release point. The FLAK gunners had to make adjustments for these variables very quickly. With zero wind, the FLAK gunners knew exactly where a bomber would release it’s bombs to hit specific military targets.

During the bombing of Tokyo, Japan, the B-29 flew so high during the bomb run that it encountered jet stream style head winds. Some head winds approached 200 miles an hour. This slowed the ground speed of the B-29 to a crawl. They even looked as if they were stationary in the sky. Had there been these types of headwinds over Berlin, B-17 and B-24 losses would have been sickening. German FLAK gunners would have ruled the day. But then again, all the mission planners had to do was change the bomb run direction and the ground speed of the B-29 became 350 MPH.

At Stalingrad, the Russians had utter thousands of anti aircraft guns firing at slow flying cargo planes attempting to support the 6th Army.It took a few years of sustaining heavy losses for the the 8th Air Force to devise better tactics. The P-51 Mustang allowed this. It was found that unleashing the P-51 ahead of bomber groups was better than fighter escort at altitude. Air superiority was achieved by killing Germans fighters on the ground and dog fights and not flying in formation with slow bombers. The Germans understood this early on during the “Battle of Britain!” They sought to establish air superiority over England by hitting the airfields over and over again. As a result of the British bombing Berlin, Hitler changed the mission to bombing London. This allowed the air fields to launch fighter strikes and kill the German medium bombers before they could kill off the British fighter force.

It took until February of 1943 for the 8th Air Force to learn what the British had learned during the London Blitz. Airfields and aircraft on the ground first, and then the bombing of military infrastructure second. Its called “Air Superiority.”

About the author

Leave a Reply