Anderson understood the bailout alternative better than most men aboard.
Only a few weeks earlier, on July 4, 1944, he had been on another Douglas mission when serious engine trouble and fire forced the crew to abandon the bomber over England. Anderson remembered jumping from approximately 17,000 or 18,000 feet and landing safely in a suburban area.
He therefore did not need anyone to explain what leaving a B-17 by parachute meant.
On August 1, the ground below was different.
The crew stayed inside.
Flying west without normal control
What followed was not ordinary two-engine flight.
Douglas had to use the tools that remained.
Anderson later summarized the situation by saying that Douglas brought the aircraft toward England using trim while operating on two engines. The bomber remained around 10,000 feet, and the crew's navigation became uncertain during the return.
Trim tabs are small control surfaces that reduce the force needed to hold a larger control surface in a given position. Under normal conditions, a pilot uses trim to relieve pressure rather than to replace the entire act of flying.
In a damaged aircraft, trim can become much more important.
A small trim adjustment may slowly raise or lower the nose.
Rudder trim can help oppose yaw.
Aileron trim can help counter a rolling tendency.
Engine power can also change direction and attitude.
If one side begins dropping, carefully changing power on the operating engines may help alter the forces acting on the aircraft.
None of those methods gives the pilot the fast, direct response of an intact control system.
Everything becomes slower.
Everything must be anticipated.
Douglas had to think ahead of the airplane.
If the B-17 began drifting away from the desired course, he could not wait until the error became large. Correcting a large error might demand control movement that no longer existed.
The safest path was to prevent large errors from developing.
That meant gentle changes.
It also meant accepting that some desired movements might simply be impossible.
The bomber had another problem.
Altitude was becoming a limited resource.
The crew had already descended roughly 10,000 feet while dealing with the engine fire. With two engines gone and another in questionable condition, the B-17 could not simply climb back to its previous height.
Altitude provides time.
A healthy bomber at 25,000 feet can lose power and still glide for a meaningful distance.
A damaged bomber at 10,000 feet has fewer choices.
Every mile flown while slowly descending reduces the distance between the aircraft and the ground.
Douglas did not merely have to point west.
He had to reach the Channel before the airplane used up the altitude remaining beneath it.
Then he had to cross the water.
The route home was not clean
Navigation during a wartime bomber mission was difficult even when the aircraft remained in formation.
Douglas's crew was now separated from the normal security of that formation, operating lower than before, damaged, and focused on keeping the airplane alive.
Anderson later remembered that the navigators became disoriented during part of the return and that the aircraft passed near the Caen area. He recalled antiaircraft bursts appearing around the bomber even though the crew had already survived the worst damage over the target.
The geography mattered.
By August 1, the Allied armies had established themselves in Normandy, but the front was moving through a complicated battlefield. Friendly and German forces occupied areas that could not be understood simply by looking down from several thousand feet.
A damaged bomber drifting away from its planned route could still find itself over hostile weapons.
The crew could not assume that surviving Villaroche meant the shooting was finished.
Every flak burst carried a new threat.
Another hit did not need to destroy the entire airplane.
It might only need to damage the remaining engine controls.
It might cut an electrical connection.
It might start another fire.
It might destroy the automatic-pilot components on which Douglas now depended.
That is why seemingly modest damage can become fatal in an aircraft already wounded elsewhere.
An intact B-17 had redundancy.
43-37892 was using up that redundancy mile by mile.
The bomber's four engines represented one layer.
Two were already gone.
The remaining power was another layer.
One surviving engine was weakening.
The manual control system represented another layer.
Parts of it had been shot apart.
The automatic pilot represented another layer.
Douglas was relying on it because he did not trust the manual system.
Fuel tanks, electrical circuits, structural members, instruments, and propeller systems all formed additional layers.
Each new hit threatened a system that might already be serving as the backup for something else.
For the men inside, that meant the airplane could appear to be flying normally for a minute while being only one failure away from becoming uncontrollable.
There was no way to inspect every damaged area in flight.
Nobody could crawl onto a wing and examine an engine mount.
Nobody could measure every cracked fitting.
Nobody could trace every severed cable while the airplane shook through hostile air.
They could only respond to what the bomber told them.
Vibration.
Sound.
Instrument readings.
Smoke.
Fuel smell.
Engine temperatures.
Changes in attitude.
The B-17 had become a machine giving warnings from several directions at once.
Douglas had to decide which warnings mattered most.