SBD Dauntless

[Guroburov]

Hey Uncle Fireball,
As you say, the plane had a range of 250 miles with the 1000 lb bomb but extended to 325 miles with a 500 lb load. So there was no real reason for them to not be able to carry the heavier bomb other than a desire to extend the range by lowering the bomb load. Unless you want to reload the scouts to keep scouting for more targets.

[panzergator]

It may have required a change to the trapeze that carried the bomb clear of the propeller arc to accommodate the larger bomb. I'm guessing Douglas had that covered.

[chrisswim]

From some reading, including War in the Pacific, Scouts did not always carry a bomb. Later, some fighters were used a scouts and as dive bombers since they were faster, and had longer range.

[panzergator]

Changing a trapeze may not have been necessary, depending on bomb fittings, or may have been fairly simple, if Douglas Aircraft was smart with the design.

[panzergator]

I haven't found any reference to changing the trapeze. Probably one size fits all?

[Nepty]

Once the scout bombers spotted the enemy fleet they would radio back to the carrier their position and then try to attack. After they dropped their bomb they would head back to the carrier if they were still alive. By the time they got back to the carrier if their carrier was not sunk or badly damaged or undergoing attack, they could rearm with 1000 pd bomb but most likely the battle would be over by then unless the enemy was real close, not likely.
The fleets would most likely move away from each other once they knew they were spotted or attacked unless one got the advantage over the other then they might close to finish them off. The one that spotted and attacked first usually had the advantage. The fleet that was spotted or attacked usually got the hell out of there as fast as they can.


Nepty

[piersyf]

I could be a bit off base here, but here goes; the Dauntless squadrons at Midway were divided into scout squadrons flying the SBD-2 and didn't carry anything over a 500lb bomb. They could carry 2 100lb bombs on the wings, seem to have done so for the first strike, then just 500lb after that.

The bomber squadrons were flying SBD-3 with 1000lb centreline bombs only, so it could be more a frame loading issue than anything to do with the trapeze.

SBD-5 and above could carry up to 2,250lb of bombs.

SBD pilot's notes refer to ANY aircraft carrying a bomb as a 'bomber' and scouts as carrying fuel tanks.

So... pure speculation but I'd say it comes down to 2 options; capability of the mark (using the older models as scouts because they can't carry as much) or doctrine (limit scouts to lighter loads so they don't forget their main role [doubtful] or logistics restraints [carriers can only carry so much] but that is dependent on the availability of resupply).

[Donald M. Scheef]

Early in WWII the Japanese Navy used the Nakajima B5N [Kate] torpedo bomber for carrier-based reconnaissance. The Kate had a significantly greater range than the Aichi D3A [Val] dive bomber.
From mid-1942, the Yokosuka D4Y1-C [Judy] began to enter service. This was a dedicated reconnaissance aircraft - the early-model D4Y models were intended to be dive bombers but were ineffective in this role. Later-model Judys with radial engines were effective dive bombers.
In late 1944 the purpose-built Nakajima C6N [Myrt] entered service. This was a pure reconnaissance aircraft with no offensive weapon capability.
Don S.

[piersyf]

If you're using counters, stack them. Have one for the aircraft and one for the load. List performance loss on the load counter. Once the load is dropped, remove the counter.

Forgot to say before, SBD cruise speed was 200kts with no bombs, 190kts with bombs, according to the pilot's notes.

[Mk 1]

Interesting discussion so far. I do not claim too great an expertise on naval matters, but as an avid reader of WW2 history in general might offer at least a few added points.

Once the scout bombers spotted the enemy fleet they would radio back to the carrier their position and then try to attack. After they dropped their bomb they would head back to the carrier if they were still alive. By the time they got back to the carrier if their carrier was not sunk or badly damaged or undergoing attack, they could rearm with 1000 pd bomb but most likely the battle would be over by then unless the enemy was real close, not likely.

This presumes a carrier-vs-carrier engagement. A valid model, to be sure, but not the dominant use case. Coral Sea, Midway, and Leyte Gulf all stand large in our thinking. But carriers were engaged in dozens and dozens of combat actions, not just these three.

Don’t just think in terms of the game you want to play. Allow yourself to consider all the scenarios that naval aviation doctrine needed to consider. Then the differences between scouting squadrons and bombing squadrons becomes clearer.

If you want to find cruisers, radio picket ships, torpedo boats, subs running on the surface, merchant ships (solo or in escorted convoys), or any of a dozen possible floating targets of interest, having your planes fly over more sea makes a big difference. Being able to deliver a meaningful punch at the time and place were you find a target of interest also matters. Calling for someone else to come with a bomb an hour later means a target that might be anywhere in 2-3,000 sq. miles of ocean, or underwater, or hidden along a tropical shoreline, by the time your strike arrives.

The fleets would most likely move away from each other once they knew they were spotted or attacked unless one got the advantage over the other then they might close to finish them off. The one that spotted and attacked first usually had the advantage. The fleet that was spotted or attacked usually got the hell out of there as fast as they can.

Nepty is this your own sense of what carrier fleets should have done, or an actual reading from history of what they did?

My understanding is that what actually happened was usually the opposite.

It is my understanding that both sides tried to steer towards the reported enemy fleets at Coral Sea (within the limitations of launching into the wind, and bearing in mind that both sides got poor scouting reports of course). At Midway Nagumo very definitely steered to close with the reported sightings of the USN carriers, and many consider that to have been one of his fundamental mistakes. IJN strike aircraft out-ranged USN strike aircraft, and if Nagumo had stayed out along the edge of USN strike range he could have done notably better. Of course the initial position reported by the scout was off by something like 60 miles, so even if he had stayed out at what he thought was his effective “immunityâ€￾ zone, he would still have been vulnerable. But only if the USN strikes flew directly to him in a straight line, which we know some of them they didn’t.

500 pound bomb for initial scouting mission and 1000 pound for the second strike if like nepty said anyone survives.

It might also be worth considering that carriers did not carry unlimited stores of munitions. If half the bombs were 500lbrs, and a portion of each weight class were HE vs. semi-AP, then there might well not have been enough 1,000 semi-AP bombs to load them up on all the planes for a second strike.

At Midway, at least, it is my understanding that the location of the enemy fleet did not come from the USN carrier’s own scout bombers. Quite to the contrary, the enemy’s location was found and reported by shore-based assets, so scouting, bombing and torpedo squadrons all took off with the deliberate intention of making a strike. Even so, I believe (not too sure, so feel free to check me on this) that the scouting squadrons flew with 500lb bombs (and perhaps 2 x 100lb under the wings).

One last thing, on the scouting mission they would not have any fighter cover would they?

My understanding is no, scouts didn’t get escorts. There are a few reasons.

- A plane at 10,000 feet is likely to spot a ship before the ship spots the plane. In the time it takes a scrambled fighter to get to the altitude of the scout, the scout can be long far away and in or behind clouds.

- If you put your fighters out on scouting missions, who is left to escort your strike when you DO spot an enemy carrier? Who is left to protect your own fleet?

- Flying boats and float planes regularly conducted scout missions without escort. Carrier scout planes were substantially more nimble and able to take care of themselves. Escorts were really only for pressing home your mission (staying on the fleet for some time, or closing for the attack, despite enemy fighters).

It is worth bearing in mind that USN carriers considered the Dauntless to be a carrier defense asset too. If an enemy strike was inbound, the Speedy-Ds would be next in line after the fighters to launch and bolder the intercept strength. So also with Vals in the IJN carriers (although they were not scouts, so not quite as relevant to the discussion).

Of course all of that changed as airsearch radar became available and fighter control centers were organized aboard the carriers. Suddenly the ships could see the planes before they could see the ships, and fighters could be vectored towards the interlopers before they even knew they were at risk.

So everything seems to be pointing to 1000 pound bomb for the bombing squadrons and up to 500 pounds for the scouting or no load at all.

I think the 2 x 100lb loads were often carried as well as the 1 x 500lb. More useful for trying to get that sub running on the surface or at periscope depth that you only get 1 run at before it dives away. Subs were considered a big threat, and air scouts a prime defense.

I think in the later years US did away with the scouting squadrons but my game will depict ships up to the end of 1942 so i have to include them in the air wing complement …

In later years the US doubled their fighter strength, and in some cases eliminated dive bombers altogether, as fighters were configured to carry drop tanks for extended range, and bombs and rockets for strike purposes. Double-duty of scouting and bombing became multi-duty of fighters that could do fleet defense, escorting, scouting and bombing, and dedicated strike planes that could carry torpedoes, bombs for land strikes, depth charges for ASW, and could also do scouting.

SO for scouting rules which i'm still attempting to write it seems that the US relayed mostly on carrier based planes and flying boats …

US fleets relied on carrier based planes. Initially scouting squadrons with dive-bombers, later more often the TBF Avenger with a modest bomb load.

Flying boats were the primary scouting platform for island naval stations, due to their very long loiter times. Later in the war PB4Y “Privateersâ€￾ (B-24s in naval service) were also very common scouting platforms for larger naval air stations, due to their enormous range.

Fleets didn’t rely on these assets, but usually received messages effectively, and perhaps even coordinated search patterns with them when in proximity to naval bases.

…but the japanese used in the main battleship or cruiser launched scout planes, flying boats and only sparingly carrier based aircraft.

Doctrinally the IJN used the float planes from cruisers as a primary scouting resource. I don’t think they used battleship planes, which were reserved for spotting for long-range naval gunnery. Could be wrong on that…

The USN was a bit more concerned with finding the enemy fleet first. USN carriers operated separately, to be harder to find. Each carrier launched it’s own strike. The IJN was far more concerned with having a concentrated strike ready to go when an enemy fleet was spotted. Their carriers sailed together and launched coordinated strikes.
As experience grew, the USN adopted the concentrated carrier strike force model, but retained their focus on more carrier-based scouting.

Or so I understand. Haven’t been there nor done that. Just read about it.