De Havilland Mosquito (Wood vs. Metal)

[Reluctant Poster]

The FB.VI was the most common fighter-bomber variant, and the most produced Mosquito variant (~2,300). Apart from a few specialist versions (FB.XVIII Tsetse), other fighter-bomber variants were the Canadian (FB.21, FB.26) and Australian (FB.40) built versions of the FB.VI.

The most produced single bomber type was the B.XVI, with 400 built. However, the Canadian built B.VII, B.XX and B.25 were all versions of the B.IV, but with different Packard supplied engines. There were 273 B.IV, 25 B.VII, 245 B.XX and 400 B.25 built.

And don't forget the 54 B. IXs.
The impact the bomber versions had in relation to the small numbers produced was phenomenal. Bomber Command Mosquitoes dropped more tonnage than Whitney's and Hamptons combined and were narrowly beaten by the Stirlings.

 

[Zipper730]

Bomber Command Mosquitoes dropped more tonnage than Whitney's and Hamptons combined and were narrowly beaten by the Stirlings.

You'd think the ability to escape defenses and survive to deliver the payload itself would be a major point.

 

[ThomasP]

Mossi B Mk IV
TARE___ 13,400 lbs
Light____15,318 lbs (this is with all fixed and removable equipment, but no bombs, ammo, or fuel)

 

[Zipper730]

Mossi B Mk IV
TARE___ 13,400 lbs
Light____15,318 lbs (this is with all fixed and removable equipment, but no bombs, ammo, or fuel)

Fascinating: The B.XVI seemed to have only gained 900 pounds empty (14300 lb.)

 

[FLYBOYJ]

When I say "mass", I am being pedantic. Mass is an amount of material, and the units are kilograms and slugs. Weight, the force we all exert due to gravity, ought to be quoted in Newtons and pounds. I work in engineering and I need to know where to insert G in calculations. I weigh 210lb. I have a mass of 95kg.

I get it but to keep this in layman's terms the OP was trying to determine how much heavier a metal Mosquito would be. No need to make it more complicated than what it is!

Having said that, my reference used kilograms. The information we need either is DeltaM (300kg) or DeltaW (660lb). This is an excellent argument to not bring up at your neighbourhood butcher shop. They have too many sharp implements lying around.

Yes, so keep it simple and the knives in the drawer!

 

[FLYBOYJ]

I had looked into a thread which touched upon a metal-mosquito design. It was stated here that with metal construction the plane would have been 40% heavier (WAG's often are where most guesses start lol), however I was also told that the 40% weight gain didn't factor in the landing-gear (would increase to some degree), the weight of the systems (no change), crew (no change), fuel/oil (would go up if needed to meet fuel fraction), and armament (no change).

IIRC the Mosquito landing gear was real simple, 2 struts packed with rubber "pucks." Considering some of the loads the Mosquito actually hauled, I don't know if a modified landing gear would be necessary.

 

[FLYBOYJ]

Mossi B Mk IV
TARE___ 13,400 lbs
Light____15,318 lbs (this is with all fixed and removable equipment, but no bombs, ammo, or fuel)

Using "Tare" weight is confusing. What is the "fixed" and "removable" equipment in this example? "Fixed" and "removable" can vary from aircraft to aircraft. I think "EMPTY WEIGHT" should be used.

Standard empty weight—aircraft weight that consists of the airframe, engines, and all items of operating equipment that have fixed locations and are permanently installed in the aircraft, including fixed ballast, hydraulic fluid, unusable fuel, and full engine oil.

 

[Zipper730]

IIRC the Mosquito landing gear was real simple, 2 struts packed with rubber "pucks." Considering some of the loads the Mosquito actually hauled, I don't know if a modified landing gear would be necessary.

So landing gears that fold inward or outward tend to have more of an effect on weight than ones that flip back into a nacelle?

Using "Tare" weight is confusing. What is the "fixed" and "removable" equipment in this example? "Fixed" and "removable" can vary from aircraft to aircraft. I think "EMPTY ERIGHT" should be used.

Standard empty weight—aircraft weight that consists of the airframe, engines, and all items of operating equipment that have fixed locations and are permanently installed in the aircraft, including fixed ballast, hydraulic fluid, unusable fuel, and full engine oil.

I'm pretty sure Tare means the same as Empty in the states.

 

[Shortround6]

Bomber Command Mosquitoes dropped more tonnage than Whitney's and Hamptons combined and were narrowly beaten by the Stirlings.

This takes a bit of interpretation.
Not saying it isn't true, but the number of Whitley's and Hamptons assigned to Bomber Command and for how long might bearing looking at.

For instance as of Sept 1939 the RAF ( which is not necessarily Bomber Command) had 207 Whitley's, of which 160 (minus operational losses) were the MK I-III versions with Tiger radial engines, Whitley's with Tiger engines were banned from over water flights.

Whitley's were not used on operational bomber missions after April 29/30 1942 but production continued until 1/2 way through 1943. They were used as troop transports, paratrooper aircraft, Maritime reconnaissance, cargo and other roles. Sometimes not very well.

Only about 1400 Hamptons were built and a number were built after it stopped flying with Bomber command.

The fact does help point out that the 1940-41-42 operations were done at a much lower rate than in 1944-45. That is the number of missions flown per month.

 

[cvairwerks]

So landing gears that fold inward or outward tend to have more of an effect on weight than ones that flip back into a nacelle?

The Mossie gear, being essentially a pair of struts, one on each side of the main wheel, is about the simplest retractable structure there is, and is the lightest. Gear that fold other directions are considerably heavier, as they are single sided designs. The single sided design supports the main wheel from a single side only, and therefor must have the increased structural strength and rigidity to accomplish the task. Typically, the single sided gear also incorporates a telescopic shock absorption system, which adds weight and increases the structure requirements.

Gets to be a huge balancing act to design the gear to fit the available retraction well volume and be able to support the required loads.

 

[FLYBOYJ]

So landing gears that fold inward or outward tend to have more of an effect on weight than ones that flip back into a nacelle?

Not necessarily, it will depend on the actual landing gear construction and how it is mounted within the airframe

I'm pretty sure Tare means the same as Empty in the states.

Not really - At least in the US, "Tare"(in terms of weighing and aircraft) is usually referred to something that is part of the weighing system but not part of the actual aircraft. This could be a jack (to level the aircraft) or even chocks, to ensure the aircraft doesn't roll off the scales.

AIRCRAFTWEIGHINGPROCEDURE

avstop.com

 

[gumbyk]

Pretty sure this plane used stress skin construction.

After the publicity photos it and/or it's two sisters were covered in fabric. Plane also used 40-50 gallons of resin before the fabric went on.

Fabric covering of the ply was standard procedure. It provided weather protection, and smooth lines over joins, etc.

 

[Reluctant Poster]

Fascinating: The B.XVI seemed to have only gained 900 pounds empty (14300 lb.)

Not surprising. I broke down the weight difference between an Mk V and Mk IX Spitfire base on Morgan and Shacklady and came up with this:
Engine 260 lb
Propeller 65 lb
Coolant 40 lb
Radiator system. 100 lb
Ballast. 87.5 lb
Total 552.5 lb

I believe that the 2 stage Merlins improved the Mosquito CoG so ballast wasn't necessary. The radiator and coolant would have weighed less in the Mosquito due to the closer grouping of components so 450 per engine seems very reasonable.
Rolls Royce were masters of packaging and put a lot of effort into developing compact light weight power plants,
unlike Allison.

 

[Milosh]

Tare weight /ˈtɛər/, sometimes called unladen weight, is the weight of an empty vehicle or container.[1]​ By subtracting tare weight from gross weight (laden weight), one can determine the weight of the goods carried or contained (the net weight).

So for an airplane this would mean no oil, no fuel, no coolant (???), no ammo, no pilot/crew???

 

[yulzari]

Does anyone have figures for the flax reinforced resin Gordon's Aerolite plastic Spitfire fuselage of 1940?

From the only photograph I have seen it looks like they made it as sheet assembled by riveting rather than bonding but I could well be wrong.

 

[FLYBOYJ]

Tare weight /ˈtɛər/, sometimes called unladen weight, is the weight of an empty vehicle or container.[1]​ By subtracting tare weight from gross weight (laden weight), one can determine the weight of the goods carried or contained (the net weight).

So for an airplane this would mean no oil, no fuel, no coolant (???), no ammo, no pilot/crew???

IMO yes and no -

The only time you would probably have no oil, no fuel, no coolant, no ammo, no pilot/crew is when the aircraft rolls out of the factory on to the the flight line, and even then, depending on the manufacturer, fluids might be added at final assembly.

Now for weight and balance purposes - "most" of the time you'll include oil, hydraulic fluid (and coolant) and "useable fuel." Once fuel is put into an aircraft, there is a portion of the fuel tank where unusable fuel will collect. There will be an allotment for this AKA "Zero Fuel Weight."

 

[cvairwerks]

Tare weight /ˈtɛər/, sometimes called unladen weight, is the weight of an empty vehicle or container.[1]​ By subtracting tare weight from gross weight (laden weight), one can determine the weight of the goods carried or contained (the net weight).

So for an airplane this would mean no oil, no fuel, no coolant (???), no ammo, no pilot/crew???

Nope, in that definition, the aircraft would be serviced to normal limits on oil, coolant and have all normally installed equipment onboard. Fuel in the aircraft would be limited to unusable in the tanks and whatever quantity was required to fill the lines, strainers, pumps, header tanks ect. On the pilot and dispatcher side of things, this would be the empty weight. From there, you add the crew, weapons, expendables, ADI and deice fluids and mission fuel, to get a ramp weight. From the ramp weight, you deduct the amount of fuel required for start, warm up, taxi and run up, and you then have takeoff weight. Depending on the aircraft, it can get complicated and spans several forms and charts.

 

[FLYBOYJ]

Nope, in that definition, the aircraft would be serviced to normal limits on oil, coolant and have all normally installed equipment onboard. Fuel in the aircraft would be limited to unusable in the tanks and whatever quantity was required to fill the lines, strainers, pumps, header tanks ect. On the pilot and dispatcher side of things, this would be the empty weight. From there, you add the crew, weapons, expendables, ADI and deice fluids and mission fuel, to get a ramp weight. From the ramp weight, you deduct the amount of fuel required for start, warm up, taxi and run up, and you then have takeoff weight. Depending on the aircraft, it can get complicated and spans several forms and charts.

Yep!

I worked on the P-3, B-2 and L1011 production lines. In all cases when these aircraft were rolled out of the factory floor, they had all fluids except fuel on board. IIRC the first place they went to was "fuel soak" were the fuel tanks were filled. The aircraft was not moved for a given amount of time to see if any fuel leaks were discovered. Once that was complete, the fuel was drained and then the aircraft was weighed.

 

[SaparotRob]

Yep!

I worked on the P-3, B-2 and L1011 production lines. In all cases when these aircraft were rolled out of the factory floor, they had all fluids expect fuel on board. IIRC the first place they went to was "fuel soak" were the fuel tanks were filled. The aircraft was not moved for a given amount of time to see if any fuel leaks were discovered. Once that was complete, the fuel was drained and then the aircraft was weighed.

COOL.

 

[SaparotRob]

The L-1011 was a great plane at the wrong moment.