Most, if not all AA guns were unable to be elevated more than 85 deg. The manually-operated guns were also pain to accurately train at really high angles, due to human anatomy. The near-vertical dive should allow for almost 10 deg wide cone where target's AAA would not present as much as a threat as shallow dive, let alone a slow and low level approach as done by most torpedo bombers.
How fast do dive bombers dive?
- Thread starter cherry blossom
- Start date
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Most, if not all AA guns were unable to be elevated more than 85 deg. The manually-operated guns were also pain to accurately train at really high angles, due to human anatomy. The near-vertical dive should allow for almost 10 deg wide cone where target's AAA would not present as much as a threat as shallow dive, let alone a slow and low level approach as done by most torpedo bombers.
Maybe I missed something but I don't see anything in the Pilot's Notes to that effect. The Secret Years, p.294 states:
P1767 was lighter than the later models, but the speeds recorded were still well under the permitted limits. During the later tests P1767 had been modified to Mk II standards and was somewhat heavier and recorded 280mph in the dive (as noted above).
Many of the RN's destroyers were using their 4.7" guns as 'anti aircraft' guns, and well into the war too. These had a maximum elevation of 40 degrees making a vertical dive bomber almost invulnerable.
Cheers
Steve
SOP for most ships was to engage dive bombers with predicted fire while they were flying level prior to the dive and then switch to "barrage fire" when the aircraft went into it's dive. Barrage fire entails firing shells to burst above the target ship so that the dive bombers must fly through the bursts as they descend to their bomb release height. 40 deg elevation guns could participate in predicted fire (depending on range and target altitude) and barrage fire.
Predicted fire (guns controlled by an AA firecontrol computer) was almost impossible against diving targets, because of the short times involved prevented computer solutions and the complex geometry made target tracking too difficult. Assuming the target ship's guns could elevate sufficiently, the target would typically be engaged with barrage fire, or local controlled aimed fire.
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FLYBOYJ
"THE GREAT GAZOO"
What does the pilots' notes say??? That the only real and official source for this discussion.
Illustrious had 80 deg elevation on her 4.5in guns. Her accompanying destroyers did engage the attackers with predicted fire and barrage fire, but as during many of the Pacific war carrier battles, a determined DB attack will get through.
View attachment 225534
Pilot's notes (Feb 1945) state that the IAS Vmax during a dive is 315 knots or 260 knots with dive brakes; the earlier editions state the same.
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FLYBOYJ
"THE GREAT GAZOO"
Then that's the real source. BTW there's a copy on this site.
http://www.ww2aircraft.net/forum/ot...tech/upload-pilots-notes-barracuda-25827.html
I believe the dive brakes will keep the aircraft at Vmax providing you're working within the parameters of the pilot's notes (2,000 rpm). Beyond that it's questionable as it would be in any other dive bomber of the period.
Shortround6
Major General
For AA work from ships please remember that the ship is rolling and/or pitching while at sea (out of harbor) which is going to have some serious effects on high elevation fire. Training is also a pain the arse. You want to move the gun barrels just a bit to the left even at 80 degrees? you have to change elevation as the gun mount rotates to keep the guns pointed near the same point in space.
The US 1.1 gun mount was specially built to combat dive bombers an could slew the guns 15 degrees either way independent of training the mount.
Note the gear rack and pinion that allows this.
The US 1.1 gun mount was specially built to combat dive bombers an could slew the guns 15 degrees either way independent of training the mount.
Note the gear rack and pinion that allows this.
FLYBOYJ
"THE GREAT GAZOO"
I pulled a flight manual for the SB2C-5 (AN 01 25AD-1) and there's nothing that specifies that, although there's also no section of flight limiatations. There are dive angle charts at the rear of the document that provides airspeeds based on weight, configuration and dive angles, again, nothing addressing DB effectivness.
AN 01-25AD-1 Prelininary Pilot's Handbook of flight operating Instructions SB2C-5 Airplane
And the predictive fire was limited by the predictive abilities of the fire control system. We know how well the RN's systems worked against aircraft diving at over 350 mph at 80 or 90 degrees. Illustrious was equipped with more modern equipment and I guess others in the task force (Warspite, Valiant?) were too. I have no idea how her close escorts like Hasty and Jaguar were equipped. It didn't stop Illustrious being reduced to a floating liability in six and a half minutes.
Cheers
Steve
Cheers
Steve
Can you name any dive bomber attack on a carrier that was stopped by AA? NO WW2 AA system had the capability to defeat a determined DB attack, even with considerably larger numbers of defending ships than were present when Illustrious was attacked.
What makes you say that?
FLYBOYJ
"THE GREAT GAZOO"
It's in the pilot's notes - para 42 p16 - you start your dive with a power setting of 2000 rpm. It gives the entire process for diving and seems to be revised for the March 1943 issue we have posted in the technical section of this site.
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FLYBOYJ
"THE GREAT GAZOO"
Because at that given RPM you are not going to build up speed to exceed Vne or Vmax. Remember the aircraft has a constant speed prop that will act like your transmission when you downshift while going down hill. You also control speed by how far you lower the nose in the dive. if you go to the pilot's notes it provides all the parameters and in theory if you follow these instructions there should be no issues in operating this aircraft.
CharlesBronson
Senior Master Sergeant
Interesting detail.
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A forgotten divebomber of ww2 is the A-36 Apache or Invader, being basically a converted fighter I guess its vertical bombing speed should be very high. And yes... the dive brakes are precisely made to avoid the aircraft to achieve terminal speed.
FLYBOYJ
"THE GREAT GAZOO"
Maybe, maybe not - look in the POH. I'm on the way out, I'll engage later.
FLYBOYJ
"THE GREAT GAZOO"
I looked at the POH posted here, it's incomplete and does not show flight limitations. According to internet sources, max dive speed was 390 mph
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