Getting P-40 into the air quickly

[GrauGeist]

Bear in mind that the warhead of a torpedo is a fraction of the overall weight.

For example, a US Mark 14 weighed 3,200 pounds, but only had a 640 pound warhead.
So delivering a 500 pound bomb alongside a ship would prove to be comparable to a torpedo hit, either in direct contact or a near-miss detonation that results in hydraulic damage to the ship.

 

[pinsog]

Bear in mind that the warhead of a torpedo is a fraction of the overall weight.

For example, a US Mark 14 weighed 3,200 pounds, but only had a 640 pound warhead.
So delivering a 500 pound bomb alongside a ship would prove to be comparable to a torpedo hit, either in direct contact or a near-miss detonation that results in hydraulic damage to the ship.

 

[The Basket]

Torpedoes are big heavy things that cost a lot and not every aircraft can carry them. You have to fly low and slow to drop them and even if you dropped it perfectly then still won't work. So skip bombing is a better bet than a torpedo certainly USA airplanes in early part of Pacific war.

Don't need AP against an unarmoured Hull of a destroyer or merchant but you don't need to be the Iowa to sink merchants so I would be skeptical of the value of skip bombing against more substantial capital ships unless I stand corrected.

 

[Navalwarrior]

Too lazy to look because my books are way over there----------------------------------------------> but were the aircraft at Pearl armed?

Resp:
Reports I read indicated most were not armed, but of those that were . . . were the 30 cal wing guns. So Welch and Taylor did battle w/o their 50 cal nose guns!

 

[Reluctant Poster]

The following link is to another website with a much more involved discussion of skip bombing
Skip Bombing - Axis History Forum

 

[Schweik]

Very interesting...

 

[Schweik]

A link in that thread goes to another which indicates that the Soviets used A-20 skip-bombers to sink this German (formerly Dutch) flak cruiser. A posted from Finland wrote:

"IMO attack against Niobe was best planned and executed operation that Soviet airforce made during the Continuation war.

Pe-2s divebombed landbased (Kotka and Hamina?) flakbatteries and silenced them. While everyones attention was fixed to the high two Bostons attacked from the low using bombs that bounced from the surface of the sea and hit Niobe to the side.

Reason why Niobe was moved to Kotka was to give protection to the light surface forces (ferries, M-boats) that were employed at the bay of Viipuri, guarding the minefiels cross bay of Finland and watching after antisubmarinenet at the mouth of bay of Finland. Good book about the subject is Itämeri ja Suomenlahti 1944-45 (Baltic sea and bay of Finland 1944-45) by Cajus Bekker. It easy to get from any decent library.

And finally, how an earth the Soviet pilots couldn´t tell the difference between Niobe and Väinämöinen? At least their bombing was more accurate than knowledge of ships

"

A lot more detail here

AA-cruiser Niobe - Axis History Forum

 

[Schweik]

Apparently though 130 aircraft joined the operation, the actual strike that sunk the ship was by four A-20G's, one of which was lost. They and the 22 Pe-2s which silenced the flak batteries were the only bombers. One other aircraft was lost dropping mines.

 

[Reluctant Poster]

Here's a good synopsis of the US Air Force preparedness (lack of) on December 7
https://media.defense.gov/2010/Sep/17/2001329818/-1/-1/0/AFD-100917-040.pdf
Commander Taylor mentioned in the study had a very interesting career
Page 366
STATUS OF THE PRINCIPAL HAWAIIAN DEFENSES IN 1941

 

[Navalwarrior]

Very interesting...

View attachment 551683

Resp:
Interesting. I just wonder what year these diagrams were drawn.

 

[Reluctant Poster]

The Hart Enquiry testimonies of the men involved in the Pearl Habor AWS
INDEX TO WITNESS TESTIMONY REGARDING OPANA POINT RADAR.

 

[Reluctant Poster]

It is interesting to contemplate what the Japanese reaction would have been had the radar warning been heeded, planes scrambled, and I would presume in this instance a substantial loss of Japanese aircraft, much less damage to Pearl, and depending on the winds of luck quite possibly the sinking of a Japanese carrier or two.
What could the reaction possibly have been. " Oh sorry, just kidding. Didn't really mean it"?
I suspect they would have carried on in the Philippines etc. but seems like that would have really taken the wind out of their sales.

The much maligned Kermit Tyler talked to the radar operators at 7.20, the first bombs fell on Wheeler 35 minutes later. Even if he had the authority to launch all planes there was simply not enough time for a successful interception to take place.

 

[Reluctant Poster]

Finally for general interest, a history of fighter direction in the USN.
The Beginnings of Naval Fighter Direction - Chapter 5 of Radar and the Fighter Directors - Engineering and Technology History Wiki
I also recommend
Amazon product ASIN B01MR4G2EZ

 

[Navalwarrior]

The much maligned Kermit Tyler talked to the radar operators at 7.20, the first bombs fell on Wheeler 35 minutes later. Even if he had the authority to launch all planes there was simply not enough time for a successful interception to take place.

Resp:
Tyler had just arrived at Pearl Harbor for assignment. He was told B-17 would be arriving. The Japanese attacked from almost the exact coordinates as the arriving B-17s. My hat is off to the radar operators, as they stayed on station after their designated shift ended and reported what they saw. Like Reluctant Poster said, it likely wouldn't have made much difference.
As for the relief of Kimmel and Short, it was more of 'standard operating procedure' in doing so. I believe MacArthur should also have been relieved. His 'air' General went to see MacArthur three (3) times, but MacArthur refused to see him. Why the AAF General didn't activate some form of 'search and attack' on his own is unbelievable. His lack of action enable the Japanese to destroy nearly all of MacArthur's air power 'on the ground!'

 

[Navalwarrior]

Very interesting...

View attachment 551683

Resp:
I am recalling this story by memory of several years, so I may have some details a little off. It was during the Korean War that a former WWII US Naval Aviator proposed 'skip bombing,' but not against ships. Naval aircraft were performing power projection in support of ground forces. Ground forces were already established, so they were picking targets of opportunity or responding to requests by allied forces embedded there. During egress one day, US Naval aircraft spotted a train heading toward a mountain tunnel. They could only watch as they had depleted their ordinance. Also, the train would wait out the aircraft by hiding in the tunnel.
A plan was proposed to not only get the supply train but to blow up the tunnel. But the question for Naval Air Power was how to do it. In short order, it was found that 3 officers assigned to this aircraft carrier wing had training in 'skip bombing' during WWII. As it turned out, the aircraft carrier still had ordnance left over from fighting the Japanese; several aerial torpedos. The plan was to skip the bomb the torpedos down the tracks at the opening of the cave, once the train entered the tunnel. Eventually the Admiral on board agreed to let these three pilots try. Several days these pilots practiced skip bombing w/ empty modified torpedos, thereby calculating the best speed and angle of attack.
It took several days to determine when the train would most likely pass through. After a few flights three attack aircraft (sorry, type was not mentioned) spotted the train. Making sure the train saw them, the train stopped well inside the mountain, thinking it would be safe. Attack aircraft 'skip bombed' their ordnance into both openings in the mountain, where the explosions sealed both openings! Result: scratch one supply train and one hiding place!

 

[Reluctant Poster]

I just loaded the aircraft with what I was told to load it with, no one asked my advice. That was decided way above my pay grade.

But IMO, and just IMO, a AP bomb used in the ship bombing at 250 mph isn't going to have nearly the penetration as it would in the verticle mode.
For instance the Dauntless was limited in it's dive by it dive brakes to what ? 250 mph, ??
But the centerline drop rack had the mechanism that projected the bomb to beyond the propeller diameter, because the bomb dropped faster than the aircraft, and picked up speed from the drop point till impact. Impact speed would depend on how far it fell. But I'd guess a great deal more than 250 mph.

Figure 37 in the attached shows the terminal velocity of the US 1600 lb AP vs altitude of release. I believe the figure is for level bombing, dive bombing would add the vertical component of the bomber itself.
The Royal Navy used these bombs for its attack's on the Tirpitz. The pilots were instructed to release at a minimum height of 3500 feet to penetrate the main deck armor. Apparently they released at a lower altitude and although they achieved 4 hits in operation tungsten, none penetrated. A later mission did achieve penetration with one bomb but it failed to detonate.

 

[Navalwarrior]

That's why the third strike was cancelled cos the Japanese had already achieved military objective and losses were rising so best get when the gettings good.

No way of knowing what's on the horizon or even if there was a trap out there.

My view is USA on 7th December 1941 was on peace mode. Sunday morning is lazy so plenty of troops away for the weekend, and a few troops out nursing hangovers and so compete surprise and trying to find every pilot and mech and tech to get airplanes airborne would be a haphazard task.

1 hour warning or 30 mins would have made a marginal difference.

Resp:
The official reason aircraft were bunched close together was to prevent sabotage. This was/has always been a concern. However, as you mentioned it was a weekend . . . and I believe placing the aircraft close together enabled less guards to watch them. More personnel could take time off. An AAF Colonel protested the order in writing the placing of aircraft in such close proximity, because it actually made sabotage easier, rather than making it less so.

 

[michael rauls]

The much maligned Kermit Tyler talked to the radar operators at 7.20, the first bombs fell on Wheeler 35 minutes later. Even if he had the authority to launch all planes there was simply not enough time for a successful interception to take place.

I had the ( apparently mistaken) impression that it was about 45 minutes of warning but even so seems like 35 minutes would be enough time to get at least some planes in air. Does it take more than 35 minutes to fuel up a p40 and get it in the air?
Truth is I really don't know.

 

[GrauGeist]

We should also consider the budget constraints the U.S. military was operating under prior to the war.
The U.S. was coming out of the great depression and the Army and the Navy both were operating on a shoe-string budget which in turn resulted in minimal staffing.

In regards to Michael's question - 35 minutes advance warning would have been more than enough time to get a formidable force into the air.

 

[Reluctant Poster]

I had the ( apparently mistaken) impression that it was about 45 minutes of warning but even so seems like 35 minutes would be enough time to get at least some planes in air. Does it take more than 35 minutes to fuel up a p40 and get it in the air?
Truth is I really don't know.

There is more to than that. This was not the era of instant communication. RAF fighter command could do it but they were on a war footing and set up for instant response. The ground crews were billeted right by the aircraft, the pilots nearby ready for action. At 7.20 AM every one in Pearl is asleep, how do you get them down to the airfield in time to do anything?
Note that just getting them into the air in 35 minutes doesn't help, you have to intercept well before they arrive over target. The USN found from experience that at least 30 miles was the distance required with an altitude of 20,00 feet for a successful interception.