Can the XB-19 produced in quantity?

[marathag]

I really doubt the structure could take that.

Wings were stressed to take several 'G' loads, plus around 10000HP of tractor thrust.
Would be about the most useful task the external shackles could be set to.
Any rocket is just a mix of thrust over time. Not a problem, as you aren't going for something with a second or two burn time, like SAM booster stages

 

[marathag]

Yes I understand, but there's not a lot you can do with a mid-30s airframe that's obsolescent by the start of WW2. Really other than transport (where it'd be mediocre anyway) and ASW (where it might actually be useful) the plane is a white elephant.

Why mediocre? The XB-15 got a real cargo door. And then overhead track system for moving cargo around. Same could have been done with the -19

 

[WaterproofPotatoes]

For all you aeronautics types out there; could you add a liquid cooled driving a pusher prop to the inboard engine nacelle to create a six-engined version?

If I could play around with making a YB-19A, I would take the KISS approach with a lot of things. It will still be a big plane and neither fast nor maneuverable, but there is some potential still.

If it were me, I'd just change the spacing of the original 4 engines and go with 6 Double Wasp radials in tractor configuration, preferably the 2500 hp ones if I could get my hands on them. Perhaps too much hindsight is involved, but I would also remove the bunks and galley to save weight, move all fuel and bombs inboard and dispense with all external hard points except for drop tanks for VLR missions over the Pacific.

I would also simplify the armament from 5x .30 cal, 6x .50 cal and 2x 37mm. .30 cal lacks the range and punch, 37mm is too slow for fighters. Eliminate all hand-swung guns except in cheek positions and go with 12x .50 cal, or later, 12x .50 cal + 1x 20mm in the tail. All twin-gun power turrets in the nose, tail, dorsal, ventral and top positions for remaining 10 guns.

 

[TonyA]

If I could play around with making a YB-19A, I would take the KISS approach with a lot of things. It will still be a big plane and neither fast nor maneuverable, but there is some potential still.

If it were me, I'd just change the spacing of the original 4 engines and go with 6 Double Wasp radials in tractor configuration, preferably the 2500 hp ones if I could get my hands on them. Perhaps too much hindsight is involved, but I would also remove the bunks and galley to save weight, move all fuel and bombs inboard and dispense with all external hard points except for drop tanks for VLR missions over the Pacific.

I would also simplify the armament from 5x .30 cal, 6x .50 cal and 2x 37mm. .30 cal lacks the range and punch, 37mm is too slow for fighters. Eliminate all hand-swung guns except in cheek positions and go with 12x .50 cal, or later, 12x .50 cal + 1x 20mm in the tail. All twin-gun power turrets in the nose, tail, dorsal, ventral and top positions for remaining 10 guns.

For defensive armament, I would just go with same suite as the Privateer.

 

[WaterproofPotatoes]

For defensive armament, I would just go with same suite as the Privateer.

For maritime patrol sure, but for over Europe, I'd want the ball turret to cover the behind-and-below arc and to dispsense with the blisters that add a lot of drag.

 

[Peg Leg Pom]

For maritime patrol sure, but for over Europe, I'd want the ball turret to cover the behind-and-below arc and to dispsense with the blisters that add a lot of drag.

It better not try going anywhere in Europe in daylight

 

[WaterproofPotatoes]

It better not try going anywhere in Europe in daylight

Certainly not without an escort! I'd also want it to be able to cruise at around 200mph minimum, and have the B-17's ~35 000 foot service ceiling

 

[marathag]

For maritime patrol sure, but for over Europe, I'd want the ball turret to cover the behind-and-below arc and to dispsense with the blisters that add a lot of drag.

Privateers didn't lose much speed from the blisters. open windows in handheld guns caused more drag.

Ball Turret was least effective of any position on B-17s and B-24.
By end of the War, many B-24 groups removed them, and the waist guns being the 2nd lest effective, left one gunner behind

 

[WaterproofPotatoes]

Privateers didn't lose much speed from the blisters. open windows in handheld guns caused more drag.

Ball Turret was least effective of any position on B-17s and B-24.
By end of the War, many B-24 groups removed them, and the waist guns being the 2nd lest effective, left one gunner behind

Interesting! I was always under the impression that the waist guns were the least effective- and that they were a significant source of drag. Now that I think about it, the Germans focused on frontal attacks for daytime, because it minimized the time exposed to defencive fire, and (perhaps apocryphally) had better chance of killing the pilot and/or copilot. The ball could be dispensed (or B-24 retractable ball used) with and blisters retained.

 

[marathag]

It better not try going anywhere in Europe in daylight

Lucky they have nightime over there. French had a single Farman 223 put two tons on Berlin at nighttime.

 

[marathag]

Interesting! I was always under the impression that the waist guns were the least effective- and that they were a significant source of drag. Now that I think about it, the Germans focused on frontal attacks for daytime, because it minimized the time exposed to defencive fire, and (perhaps apocryphally) had better chance of killing the pilot and/or copilot. The ball could be dispensed (or B-24 retractable ball used) with and blisters retained.

HEADQUARTERS 2D BOMBARDMENT DIVISION
AAF 147 APO 558
21 MAY 1944



SUBJECT: Removal of Lower Ball Turret in B-24 Aircraft
TO : Commanding General, Eighth Air Force, AAF Station 101, APO 634

1. Operational experience in B-24 aircraft in this Division has increased the belief that under present combat conditions, the benefit derived from the Sperry ball turret may not be commensurate with the weight and parasite drag involved in this installation. Many of the group commanders wish to have the opportunity of removing this turret in at least some of the aircraft in each formation to improve the performance and the ability to maintain tactical formation with improved altitude performance, gas consumption, engine performance, etc.

2. This Headquarters concurs with this belief and is of the definite opinion that increased overall efficiency in operations may be achieved through the removal of the ball turret.

3. Some of the facts pertinent to the decision to remove the ball turret are submitted:

a. An estimate of the weight eliminated and of the effect of the C.G. on B-24H and B-24J aircraft is as follows:

WEIGHT C.G. LOCATION
(LBS) % M.A.C.
TYPICAL TAKE-OFF CONDITIONS
(Combat crew, 6,000 Ibs bombs, 6,000 rounds ammunition and 2,700 gallons fuel)
With Ball Turret 65,445 32.3
Without Ball Turret 63,945 28.9
Weight saved 1,500


TYPICAL LANDING CONDITIONS
(Navigator and bombardier on flight deck, tail gunner at waist position, 6,000 rounds ammunition and 500 gallons fuel)
With Ball Turret 46,245 29.7
Without Ball Turret 44,745 24.9
Weight saved 1,500

Note: The ammunition expended has not been considered in the above calculations, because of its variable aspect. It is assumed, however, that this will not materially affect C.G. since uniform expenditure throughout the ship may be assumed.

b. A statistical analysis of the combat activity of the defensive armament in this Division is as follows:

(1.) 6 MONTHS - NOVEMBER 1943-APRIL 1944
-------------------TOTAL-----%-OF-----------DESTROYED-----PROB.-DESTROYED-----DAMAGED----N0.-CLAIM
----------------- ENCS.----TOTAL ENCS.------N0.-------%----N0.---%-------------N0.-----%---------N0.---%
GUN-POSITION
NOSE------------164--------16.0-----------------72-----15.1-----18--18----------25------15.6------49------17.2
TOP-TURRET----177--------17.2-----------------75-----15.6-----20---20 ---------31------19.4------51------18
BALL-TURRET-----53---------5.1-----------------30-------6.3------3----3------------7------4.4-------13------4.6
LEFT-WAIST----158--------15.6------------------85----17.8-----13 ----13----------24-----15-------36-------12.7
RIGHT-WAIST---158-------15.6------------------66-----13.8-----19----19----------24-----15-------49-------17.2
TAIL-TURRET----312--------30.5----------------150-----31.4-----27----27---------49------30.6-----86-------30.3
TOTAL-----------1022--------100----------------478------100----100---100-------160------100--- 284----- 100

(2.)-MONTH-OF-APRIL-1944
------------------TOTAL-----%-OF-----------DESTROYED-----PROB.-DESTROYED-----DAMAGED----N0.-CLAIM
----------------- ENCS.----TOTAL ENCS.------N0.-----%------N0.---%-------------N0.-----%---------N0.---%
GUN-POSITION
NOSE------------74-----------20.5--------------31---19--------8------25-----------9-----15.8---------26----23.8
TOP-TURRET----75-----------20.7--------------32--19.6-------8-----25----------13-----22.8---------22----20.2
BALL-TURRET---13-------------3.7---------------5---3.1--------1------3------------2-------3.5----------5-----4.6
LEFT-WAIST-----53-----------14.6--------------30---18.4------3------9.4---------9------15.8--------11----10.1
RIGHT-WAIST----48----------13.3--------------19---11.7-------3------9.4---------9------15.8--------17----15.6
TAIL-TURRET-----98----------27.2--------------46---28.2-------9-----28.2-------15------26.3--------28-----25.7
TOTAL------------361----------100-------------163----100-----32----100---------57-------100-------109----100

 

[WaterproofPotatoes]

No contest all! Better to keep the 1500lbs in fuel, bombs or added lightness

 

[marathag]

No contest all! Better to keep the 1500lbs in fuel, bombs or added lightness

The weight saved would give another hour of flight time, that's around 160 miles, or use higher power settings and fly higher/faster

 

[TonyA]

For maritime patrol sure, but for over Europe, I'd want the ball turret to cover the behind-and-below arc and to dispsense with the blisters that add a lot of drag.

Coverage below the aircraft with the ELCO blistered gun positions was surprising and exceptionally good. The aircraft is NOT intended to operate in airspace subject to contesting by enemy fighter aircraft. Guns are provided to duel with the occasional Condor or other German VLR aircraft.

 

[M79]

The Wright R-3350 engines on the XB-19 eventually mature into forms getting almost 4000 HP (R-3350-32W: 3700 HP; R-3350-42WA: 3800 HP). But I've not seen a specification for an XB-19 using those engines.

Sub-hunting in the Atlantic and cargo hauling were some of my original thoughts, though in mass production maybe a 'B' and 'C' (or 'D'?) variant emerge with other improvements in the airframe etc. from technologies developed as the war progresses?

 

[M79]

But would be up to 7700 miles with full fuel load and a ton of bombs, so the crew would be able to go back to the galley, eat a meal, and then hit the bunks and sleep it off before finishing the mission.
When it finally got the long delayed V-3420s, cruise went up to 179mph.

Thanks! Did the altitude range change at all or was it consistent between the two engines?

Otherwise speed increases just over 32.6% for a 30% increase in horsepower. Add two more Allison V-3420s with half the speed increase for the additional two engines and if the same ratio of power increase to performance change holds steady (unlikely but for the sake of speculation...) a possible cruise speed of 234.5 MPH emerges, though a ceiling of 23k feet would remain a problem. For four R-3350-32W engines, again using the same (flawed) formula (only for the sake of speculation) cruising speed becomes about 277 MPH [284 for the 42WA], with six of these engines potential cruise speed becomes 346 MPH [355 for the 42WA]. Again, the formula I use to derive these numbers is overly simple with a lot of assumptions so it's probably off somewhat, especially with six engines, but surprisingly the R-3350 and Allison V-3420 weigh almost the same at just over 1200 kg each.

 

[marathag]

Thanks! Did the altitude range change at all or was it consistent between the two engines?

found this
Actual work to install V-3420-A engines in the XB-19 started in November 1942 at Fisher. The aircraft was redesignated XB-19A and flew for the first time with its V-3420 engines in January 1944. The V-3420 installation served as a test for the engine’s use in the XB-39. With the exception of range, the XB-19A’s performance increased across the board: maximum speed increased by 40 mph (64 km/h); cruising speed increased by 50 mph (80 km/h); service ceiling increased by 16,000 ft (4,877 m), but normal range decreased by 1,000 miles (1,609 km)

So that's a lot more altitude

 

[WaterproofPotatoes]

The Wright R-3350 engines on the XB-19 eventually mature into forms getting almost 4000 HP (R-3350-32W: 3700 HP; R-3350-42WA: 3800 HP). But I've not seen a specification for an XB-19 using those engines.

Sub-hunting in the Atlantic and cargo hauling were some of my original thoughts, though in mass production maybe a 'B' and 'C' (or 'D'?) variant emerge with other improvements in the airframe etc. from technologies developed as the war progresses?

What would the service ceiling be for a 6 radial engined variant be?

 

[M79]

found this
Actual work to install V-3420-A engines in the XB-19 started in November 1942 at Fisher. The aircraft was redesignated XB-19A and flew for the first time with its V-3420 engines in January 1944. The V-3420 installation served as a test for the engine’s use in the XB-39. With the exception of range, the XB-19A’s performance increased across the board: maximum speed increased by 40 mph (64 km/h); cruising speed increased by 50 mph (80 km/h); service ceiling increased by 16,000 ft (4,877 m), but normal range decreased by 1,000 miles (1,609 km)

So that's a lot more altitude

So cruising speed went from 153 MPH to 203 MPH, max speed from 224 MPH to 264 MPH, service ceiling went from 23,000 feet to 39,000 feet, and range decreased from 5200 miles to 4200 miles. Interesting, but the specific fuel consumption for the Wright R-3350 at cruise is supposed to be about 0.4 lb/hp/hr while that of the Allison is supposedly 0.41 lb/hp/hr with that extra 600 HP making the difference (though at max power their reliability and performance could became unstable very quickly).

What would the service ceiling be for a 6 radial engined variant be?

Good question, though apparently an excess of 40,000 feet would be reasonable and 45,000 feet would not be out of the question. Using the SWAG formula from before approx. 45,500 feet for the Allisons (still higher for the 32W). I seriously wonder what changes the airframe might see in early wartime aluminum alloys...