The Battle of Midway, the Mariana’s Turkey Shoot, the devastating air raids on Henderson
and Wewak – Documentaries will always tell you about the big battles, about the numbers
game, about the dozens of carriers and thousands of aircraft that outnumbered, outperformed
and outfought the Japanese during World War 2 – and of course we overlay that with some
emotional, bombastic music to make us all feel good.
Ever ask yourself the question: How did the US sustain this force?
How did they keep all these planes flying?
How did they manage to go from bloody battle to bloody battle and somehow just get stronger
and stronger?
The documentaries won’t tell you, I will.
Welcome to Military Aviation History.
When Japan attacked Pearl Harbor in 1941, the US Navy operated seven Carriers and one
Escort carrier, with a force of roughly 600 aircraft.
Not half bad, it sounds impressive.
But the force had one significant problem based on the inter-war legacy: the logistic
and maintenance support infrastructure was completely inadequate.
In short, the Navy had planes to fly, but no one to keep ‘em flying.
There weren’t enough units, stockpiles or trained technicians available.
And while the force had been gearing up for a looming conflict, the expansion of training
and logistic capacities to provide a support structure was slow of the mark.
Until about 1939, most formal training centres operated on a shoestring, and even the use
of reservists didn’t hide the fact that the fleet was heavily deficient on maintainers,
repair specialists and instructors.
As Fisher tells us in his recent book Sustaining the Carrier War.
“Acquiring more pilots and aircraft had traditionally drawn the most attention from
lawmakers and Navy leadership.
Acquiring and training more enlisted technicians was not a regular point of contention.
One would be hard pressed to find anything more than a cursory note in the ‘recommendations’
section of the chief of BuAer’s Annual Report to the Secretary of the Navy prior to 1939
that simply said, ‘Provide required increases in naval personnel to support the expansion
program.’”
The Navy…on the sea…was fully staffed but on land – where the actual logistic
and maintenance support happens – it was barely making do.
In 1939 it had about 66% of the personnel it required and lacked the facilities to maintain,
repair and overhaul the required number of airframes and engines.
When you look at the truly breathtaking scale of the US Navies expansion, you can start
to see why anything but a major investment in support capacities would be detrimental
to the emerging US fast carrier doctrine.
For example, in Dec 41 the Navy had 500 fighter aircraft over eight carriers.
This not just more than doubled in a year, but by end of 43, the fighter force had increased
ten-fold and continued to grow.
The more planes, the more people, technical units, maintenance facilities and spare parts
you need – actually, this is America, I’ll get back to the spare parts.
…Let’s break this down together: In general, provided there is nothing broken,
an aircraft was slotted for an inspection every thirty flight hours.
That means it is taken off the operational rooster and given a check-up.
Before that is done, it ain’t flying again.
Then you have an overhaul: a thorough checkup where a lot of key components are replaced.
It’s again linked to flight hours but in peacetime, on average it would happen every
18 months.
And you can’t do it on the carrier, it’s a Class A overhaul – it must go back to
a shore-based facility n war time, flight hours go up quickly.
Let’s take a F6F Hellcat with an overhaul requirement after 500 flight hours.
Say a sortie lasts on average 3 hours – quick math: that gives you about 160-something sorties
before your overhaul.
Take an average of 15 flights a month, that’s 45h a month – 11 months to a major overhaul.
And now don’t just take one aircraft but hundreds that are going through this cycle
in parallel, alongside minor repairs and maintenance before they even get to the overhaul.
Unless you planes to gather dust – a grounded plane is a useless plane - you better invest
in repair and maintenance capacity.
As you can imagine, a ship the size of a carrier with the requirements of autonomous operation
will have some maintenance facilities on board.
While initially the embarked squadrons would come with their own support crews, eventually
carriers were given what was known as the CASD – Carrier Aircraft Service Division.
Specifically the Engineering Division (V-2) provided the men for direct maintenance and
repairs , workshops for more elaborate component repairs and then there was a storeroom with
a specialist storekeeper to supply spare parts.
There had also been some forward thinking – which is good because military strategy
is build strategy.
For example, Ranger laid down in 1934 had only a storage space enough for a 10% stock
of spare parts.
By the time Wasp was built, the allocated storage capacity was up to 50% for spare parts
. These organizational and construction changes
provided carriers with autonomy to do their own maintenance and repair – but this isn’t
enough because a carrier is still fundamentally limited in terms of space and facilities.
Just moving aircraft from one end to the carrier to another is already quite the undertaking
and you don’t want to have non-operational planes on a carrier.
And this is where the CASUs came into play.
The Carrier Aircraft Service Units where a major change in the capacities of the Navy
to take planes off a carrier and work on it on land, thus freeing up space on the actual
carrier.
Now, the carriers could focus on flight-related tasks and minor maintenance and repairs, while
the complex stuff was - to use a 21st Century term – outsourced.
Dozens of CASUs (TEXT: of various size) were established and they were so successful and
helpful that they even started working on the Army Air Corps/Force and Allied aircraft.
“The CASUs were mobile units that could be quickly stood-up in one area and then quickly
transferred to another as ground forces secured small islands across the Pacific.
[…] Its primary task was to maintain and repair carrier aircraft, but it was not meant
to, nor quipped to complete major overhauls.”
The overhaul part was still a problem.
Yes, the situation by end of 1942 got better in terms of maintaining an ever-increasing
number of aircraft but you still needed to overhaul airframes and engines.
You couldn’t ship everything back Pearl Harbor or State-side.
So in Summer 1943 the first Navy Aviation Repair and Overhaul Unit was set up – I
believe it is pronounced A-ROU, maybe even ARROW….
Anyway, it’s a self-sufficient unit for the assembly and repair of Navy aircraft,
plus to provide engine overhaul facilities.
I mean, …check this out, just one of the larger ones AROU 5 made over 2700 engine overhauls
-that’s 2700 engines that can keep aircraft flying.
And it is about to get even better….because, well side note: Honestly, logistics and maintenance,
it is so important, we talk about how many ships either side has, how many planes, how
many aces – none of that matters if they can’t be put into AND then KEPT in the fight
– so, as you know I like to give my sources, this book, Stan Fisher’s Sustaining the
Carrier War is an absolute gem on this topic.
Fresh off the press this year, if you want a book to understand how important this topic
is – or between us, proof to someone who is too obsessed with the kinetic part of war,
then get this book.
If that isn’t enough of an endorsement, you can get it 25% OFF because it is published
by our official partner, the United States Naval Institute Press.
Use my exclusive code to get a fantastic source at a bargain price and check out my official
reading list for more recommendations.
And I don’t think I have to say this again: but the code is good for the entire Naval
Institute Press’ book catalogue and it is valid all year round.
Like write it down somewhere and use it – 25%.
Off.
Books.
Yeehaw.
Anyway, I promised it was going to get better, and it does.
Did you ever hear of the Assembly and Repair Vessels (ARV).
Yeah, the American’s built amphibious workshop to support the island hoping campaign.
Imagine this, Japanese held island.
US Navy comes by, bombs and bombards.
US Marines land, do their thing.
LSTs land and drop off supplies.
Then, rudimentary airstrip is build and now two ARVs land – one provides immediate airframe
repair and maintenance, the other does engine repairs.
They are like the first responders –once the airstrip is improved and a CASU is set
up, the ARVs pack up and do the same thing again on the next island.
The Navy only had four operated in teams of two but c’mon, this is logistics on steroids
– and I haven’t even talked about the Escort Carriers (CVE) yet that were often
designated transports of ferry aircraft between the facilities and carriers.
By summer 1944, it was estimated that for every ninety aircraft a carrier had, it needed
to replace sixteen each month to sustain operational numbers.
Luckily for the Navy, by now the American industry was churning out so many aircraft,
that an interesting shift occurred.
For the first two-and-a-half years of the war, the investments into maintenance and
logistics had kept the Navy flying, Now the carriers were spoilt for choice.
“By 1944, it was easier to just exchange damaged airplanes with replacements in order
to keep the carrier’s air group at full strength.
With so many spare airplanes available, the Navy could simply off-load aircraft that were
not mission-capable, and replace them with new ones awaiting delivery from a local CASU.
In essence, U.S. naval aviation transitioned to a ‘throwaway’ culture in the last phase
of the war due to the abundance of available replacement aircraft”.
Consider economics…with the F6F Hellcat.
The Navy could either order two Hellcats complete with a full set of spare parts and one spare
engine a plane, or order three Hellcats with no spare parts, for the same price.
If we take the Essex’s nominal loadout, we can see that without spare parts, the US
Navy is already halfway there to finance another complete Essex loadout.
And since it is war, and the Navy still hadn’t used up the money it was given, building more
planes instead of spare parts made sense – especially as the value of a plane in operation was basically
used up after a year.
At that point, it wasn’t economical to overhaul and repair it.
So, what would you do?
Order more planes, and less spare parts.
In 1941, the Navy carrier force was dressed to impressed – but it did not have any depth.
It had to be economical with force deployment, and any major repairs and overhauls were a
significant drain on combat mass.
Two years later, an expansion in logistics, maintenance, technicians, and facilities,
build into a flexible system that suited the Navy’s carrier doctrine kept the planes
in the sky when it mattered most.
Come ‘44, the Navy could support its air groups liberally wherever it went and supply
a constant stream of replacements that instantaneously filled any gap left by operational losses
or repair/overhaul.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p. 19 Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.25-26.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.38.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.120.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.121.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p. 197.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.140.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.141-143.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.148-150.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.153.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.181.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.167.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.173.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.184.
Fisher, Stan (2023).
Sustaining the Carrier War – The Deployment of U.S. Naval Air Power to the Pacific.
Naval Institute Press, Annapolis, ML.
p.183.