Dutch ordered Douglas DB-7C aircraft as Torpedo Bombers

[MiTasol]

Don't know where you got the story from but it has been muddled in the telling.

The Dutch ordered 32 DB-7B and 48 DB-7C. It was 6 of the former that fell into Japanese hands. 4 of the remaining DB-7B went back to the US and the rest of the DB-7B (22) went to the RAAF. The 48 DB-7C on order were completed as DB-7B and shipped to USSR under lend lease. You will find the story here.

Douglas Boston

There was not a problem with the A-20 as a torpedo bomber. The USSR used plenty in that role.

And yes dropping torpedoes is more difficult. If the torpedo is dropped outwith its proper parameters it could
1. Break up on entry to the water
2. Dive to the bottom
3. Porpoise and head off in the wrong direction
4. In less sophisticated systems the pilot/bomb aimer has to mentally calculate how far ahead of the target ship to aim and in doing so judge its speed and angle. In more sophisticated systems, as employed on British Beaufighter and Barracuda aircraft there was a "computer" to help. In those the pilot pointed the aircraft at the target ship but still had to make inputs to the system. That needed judgement.

In the FAA it was felt regular practice was necessary so a synthetic trainer was created to assist.

Edit You might enjoy this about Soviet use of the A-20. Scroll down for Soviet Navy use as a torpedo bomber.

The Douglas A-20 Havoc/Boston in Soviet Service

The A-20 Havoc/Boston twin-engine multi-role aircraft had a laudable service record in World War II. From its brief service with the French Armée de l’air before the Fall of France in 1940 th…

vvsairwar.com

And the RAAF were training their Beaufort crews on torpedoes so probably decided that one type was enough at that stage

 

[Sydhuey]

Bit late but, at the end on 1942 RAAF HQ found 22 torpedo sets for Boston's and notified 22 Sqn of the fact , by then the DB-7B's with 22 sqn had been converted to the low level Strafer/Attack role and they quietly ignored the fact Torpedo kits were available , Torpedo attacks was the realm of the Beaufort the Boston was much better in the low level fast attack role.

 

[MiTasol]

You might find more on the Dutch DB-7s in Peter Boers book. I do not have a copy but I do have the erratum which I have attached.

As you can see in that document he is very determined to make the book as accurate as possible.

 

[Fatboy Coxy]

Does look a like a good book to have, unfortunately, the few copies available are going for a small fortune.

 

[EwenS]

One to look out for:-
Amazon product ASIN 1804512087
View: https://www.amazon.co.uk/dp/1804512087/?coliid=I2JGVQUL4PRKQF&colid=I38YUH7DZNUG&psc=0&ref_=lv_ov_lig_dp_it
Not sure when it will now be published as it doesn't appear on the Helion website any longer.

Helion is publishing quite a number of interesting books on lesser known aspects of WW2 as well as various post WW2 wars.

https://www.helion.co.uk/?sid=6cb8e3b5850255b24ed43fde0d1c8b5b

 

[Geoffrey Sinclair]

NEI DB-7B, Boeing built, contract F-672, Delivery Logs say AL347 accepted 4 November, AL358, AL361 to AL369 accepted 10 to 17 November 1941 and AL457 accepted 31 December 1941, total 12, the USAAF export report says 11 accepted in November 1941, 11 exported in February 1942.

Douglas built, contract F-719, AL887, AL889 to AL907, accepted 17 to 19 November 1941, total 20 with AL889, AL896, AL900, AL901, AL903, AL904 and AL906 marked Los Angles T (2-18). AL902 crashed in US 10 December 1941, wrecked, AL905 crashed the same day, level 4 damage. The USAAF export report has 18 accepted in November 1941, with 6 exported in January and 11 in February 1942, total 17

The RAAF ended up with AL347, AL358, AL361 to AL369, AL887, AL890 to AL895, AL897 to AL899 and AL907, total 22. Leaving AL457, AL889, AL896, AL900, AL901, AL903, AL904 and AL906 to be accounted for. If the export report is correct, 2 of these did not leave the US for NEI.

DB-7C, contract D-48/NI 41-124 (D-40), 48 DB-7C (ex model 421?) accepted May and June 1942, serials D6525 to D6312 (D-79 to D-126?). Export report says 1 to USA 47 to Russia, 46 exported June to August 1942, final one in December. Delivery logs say all to Russia.

Anybody have an interest in the engine numbers of the DB-7?

USN Model	Model	BD-2/A-20B
Date	Date	1-May-43
Loading Condition	Condition	Torpedo
Gross Weight	Pounds	21,500​
Empty Weight	Pounds	14,669​
Fuel	Gallons	494​
Fixed Guns	Type	2x0.50, 2x0.30
Fixed Guns Ammunition	Rounds	400/0.50, 2,000/0.30
Flexible Guns	Type	1x0.50, 1x0.30
Flexible Guns Ammunition	Rounds	200/0.50, 500/0.30
Torpedo Load	No. x Type	1xMk13-1
Bomb Bay Tanks Droppable	No. x Gallons	1x100 self seal
Engine Rating	For Performance	Normal
Wing Loading	Pounds/sq. feet	46.2​
Power Loading (BHP, Crit. Alt.)	Pounds/BHP	8.4​
VM Sea Level	MPH	283​
VM	MPH/Feet	300/5,000
VM	MPH/Feet	312/12,000
VM	MPH/Feet	318/14,000
VS - Gross Weight, power	MPH	96.4​
VS - Less Fuel, power	MPH	89.6​
Time to 10,000 feet	Minutes	6​
Time to 20,000 feet	Minutes	14.8​
Service Ceiling	Feet	25,600​
Take off - Calm	Feet	1,397​
Take off - 15 knots wind	Feet	989​
Take off - 25 knots wind	Feet	757​
Climb Sea Level	Feet/Minute	1,750​
Climb	FPM/Height	1,540/12,000
Endurance - 60% VM (180 mph)	Hours/Feet	6.6/5,500
Endurance - 75% VM (225 mph)	Hours/Feet	4.4/5,500
Max Endurance	Hours	7.8​
Max Range	Statute Miles	1,190​
Max Range Average Speed	MPH	167​
Max Endure./Range Altitude	Feet	5,500​
Engine Type	Type	2 x R-2600-11
Engine Gear Ratio	Ratio	16 to 9
Propeller	Model	HS CS 3 bl., 11 ft 4 in, Bl des. 6393
Engine Rating Take-Off	BHP /RPM	1,600 / 2,400
Engine Rating Normal	BHP/RPM/Feet	1,350 / 2,300 / 0-5,500
Engine Rating Normal	BHP/RPM/Feet	1,275 / 2,300 / 7,200-12,000
Protected Tankage, Fuel	Gallons	394
Fuel Tankage Fixed Total	Gallons	394
Protected Tankage, Oil	Gallons	44

Performance data from Estimates & BD-1 take off, stall speeds

Bomb Bay: 1x100 or 1x140 gallon protected fuel tank or 10x100 or 8x300 or 3x500 or 1x1,000 pound AAF bombs or 2x325 pound depth bombs. Wings, 4x100 or 2x500 pound AAF bombs, 2x325 pound depth bombs. Under fuselage torpedo 1 Mk 13-1 or 13-2. With 2x0.5 inch MG fixed in nose, 2x0.30 MG fixed in nacelles firing aft. Maximum rounds of ammunition for 0.50 inch MG flexible gun is 400.

 

[MiTasol]

Peter Boer put the following files up on Academia.

 

[Maxrobot1]

 

[elbmc1969]

View attachment 704542

Goodness! Did the lower gun actually have some sort of sighting apparatus?