Say you’re flying a B-17 bomber, or P-47 fighter and have just landed in England after a mission over occupied Europe. What work would be done on the plane?
Were plugs changed/inspected after each mission? For the B-17, especially, what work was done to the engines?
I’m trying to appreciate the behind-the-scenes work that went on after each mission.
Good question. I’ve read a few books on the missions, but post-mission maintenance seems to ba sparse. My guess is that any damage was repaired if practical (if not, planes were often cannibalized to keep others flying), and squawks were attended to. They would have been refueled for the next mission. I thought that they were re-armed, but every documentary I’ve seen shows the bombs being loaded just prior to the mission. I’ve read about gunners bringing their ammo to the planes with them, so I don’t know if the planes’ guns would have been armed right after a mission.
Radial engines need a lot of oil, so I’d assume that was topped off. Hydraulics and the electrical system would need to be checked for damage and/or function. I don’t know what the TBO is on a Wright R-1820-39 Cyclone, but I assume worn-out engines were replaced instead of rebuilt.
I hope someone else can come along and give a more substantial answer; since now that you’ve asked it, I’m curious too.
I found that there are B-17 maintenance manuals for sale online, but none that I’ve found scanned and available for online viewing.
I would have to assume that, aside from damage repair, not the same thing is done to every plane after every flight. Certain checks and replacements are done on a schedule based on hours flown, and few or no planes in a squadron would have the same number of hours.
Try B17panels.com for scanned files of the maintenance and flight manual on the F model. Be on a fast connection, the pdf of the maintenance file looks to be about 65MB.
The maintenance manual has an “Inspections and Adjustments” section, but doesn’t list the time required to complete the checks.
Spark plugs are changed every 100 hours. Look for them under the “Ignition and Electrical Equipment” section.
Other parts are inspected at certain time intervals and changed based on wear. It notes under the “Power Plant” 100 hour checks that engines are overhauled at 500 hours.
I find the layout of the manual interesting in that it groups the checks by system, not by inspection intervals. It seems a confusing way to organize the manual because you can’t just open to a page and read off a list of inspections to be done at 50 hours. Instead you have to go to each system and look for the required checks. Seems a good way to miss stuff.
A Table of Organization and Equipment (TO&E) might give an understanding of effort to keep the aircraft flying as you could get an idea of the the number of people required to support each aircraft. The only thing I could find was the wikipedia entry on bombardment group.
Using their numbers, it looks like it took about 31 people to crew and support each B-17 in a 72 aircraft bomb group.
Former USAF, but long after WWII …
As the others above have said. … There would be a prescribed maintenance procedure for post-flight. Generally it consists of looking for battle damage, replenishing any consumables like oil or oxygen, and inspecting for general wear & tear, like brake & tire condition.
Any problems the crew wrote up in the maintenance log would be fixed if possible, as well as anything found by the maintenance post-flight.
Refueling & re-arming are part of the prep for the next mision. Those would be dealt with shortly before that mission. The reason to wait is that which weapons & how much fuel to load depend on the assignment.
For some things, such as machine gun ammo where a full load was always carried, that could be done any time between post-flight & mission loading. Likewise they might pump in 1/2 or 3/4ths of a fuel load if they knew the required load was always greater than that amount. The goal would be to spread the work over a longer time to avoid a mad crush at the end.
About 20 years ago I was at an air show with a restored B-17 that had arrived shortly before. They were filtering the engine oil through cheesecloth to check for shards of metal indicating internal engine damage. I don’t know about WWII, but these guys said they did it after each flight.
Man, I’d imagine just checking the plugs would be a bit of an undertaking since there were 72 per airplane (2 per cylinder, 9 cylinders, 4 engines). Not as bad as the post-war B-36, though, which had six 28-cylinder engines with 336 plugs!
I’ll still bet they could still change them faster than I could do the plugs on a V6 minivan, though.
First thing that popped into my head when I saw this thread is that it’s are real shame David Simmons isn’t still with us to give us a nice authoritative answer.
My grandfather, a bomber copilot/bomb aimer (Halifax III, 427 squadron RCAF) said maintenance was pretty intensive, and as he was mechanically inclined he snuck in as much participation as he was allowed, which wasn’t a lot.
Even when the squadron was involved in combat sorties on back to back days it was extremely unusual for the same plane/crew to go out two days in a row. On 15/8/44 he participated in an attack in Kiel, but his crew and plane were not involved in the following days’ attack on Soesterberg. The maintenance crews worked on the planes pretty constantly, and had time to tune them up and keep what they could in top shape.
Ditto.