Firstly the Ju-390 mission to New York in original accounts cited in the Hugo Junkers website, an acknowledged authority on Junkers aircraft, refers to a two aircraft mission to New York, which may be a hint about possible air to air refuelling en-route by another aircraft ?
It may have even been recorded in the squadron records as an air to air refuelling trial rather than "mission to New York".
I do not know that for a fact and neither does anyone else, so let us put that thought aside for a moment and look at the other facts...
BMW 801E Fuel Consumption:
The Ju-390 used six BMW 801E engines which were identical to the BMW 801D except the E version was geared for better performance at altitude. In all other regards one can consider them the same. The E version had about a 100hp superiority at altitude.
The BMW 801E had a boost function for take off, by injection of a water methanol mixture into the left supercharger inlet. This could only be used for 10-15 minutes. Only at these boost settings does the fuel consumption rise to 221 US Gals PH.
This take off boost raised power to 2,000hp at a manifold pressure of 1.56 atmospheres and 2700 RPM. Usual fast cruise settings (on the FW-190A BMW 801D) were 2100 RPM at 1450hp and 1.1 atmospheres of manifold pressure.
A climb to 19,000 feet for an FW-190A fighter with a single BMW 801D engine consumed about 16 US gallons of fuel and took about 8 minutes to reach altitude. Let us assume double that for the Ju-390. That's 192 US gals to reach 19,000 ft.
Once at altitude, the BMW 801D will use 90-103 US Gallons Per Hour (GPH) if it is used at maximum cruise speed, but the Ju-390 would not have been flown at max cruise power to New York.
Any pilot will tell you, for over water flights, you do not use maximum cruise settings. Commercial airliners will use an intermediate Economical Cruise setting, but for a military plane one uses the long range cruise setting. In the case of the Ju-390 this was 45-55 US Gals PH at around 1600-1700 RPM per engine..
This falls falls way short of the 150 US Gals Per Hour which Richard claims.
Evanglider said:
Excellent analysis, Rich.
Erich said about experts:
looking through too many google searaches on the Ju 390 and the supposed Amerika bombing or recon incident, Wikpedia in all their glory seems to tak a grat big (?) look at this. wonder whom their so-called experts are that they quote stating it could or did not happen... ?
The Real Facts
Using six engines at long range cruise of 55 US Gallons Per Hour for 32 hours equates 63,360 pounds of fuel, plus 1,152 lb for take off and climb to 19,000ft. That makes for a total of 64,512 lb fuel.
The round trip distance Richard Leonard cites (7900nm) would take a Ju-390 29 hours, or just 57,420lb of fuel plus 1,152 lb for climb to altitude.
A total of 58,572lb. Add a 10% safety buffer of 5,640lb and you get a total around 64,429lb. So this is the actual fuel weight for a mission of 7,900nm with a 10% reserve.
Add this mission fuel uptake (64,429lb) to the Operating Empty Weight of the Ju-390 gives you 151,329 lb.
Subtract 151,329 lb from the Maximum Take Off Weight (166,100 lb) leaves a payload ability to New York of 14,771 lb/6,706kg. Enough for an A-bomb.
Payload for extra Range
So we have a payload capability from Mont de Marsan to New York taking the longer route Richard perfers of 6,706kg.
There is only one type of bomb worth carrying all that distance and we know what that was. We know the equivalent used at Hiroshima weighed about 5,000kg as I understand.
Range Calculations
Richard Leonard cited the maximum range of the Ju-390 as 9,700km, 6027sm (or 5,288nm). That is wrong.
He starts by subtracting fuel reserves from the lesser maximum payload range and then proceeds to get it wrong about fuel consumption by the engines.
A round trip mission of 7,900nm was well within the maximum fuel range of 8,710nm.
Incidentally the direct distance is only a mere 6,230nm, but to save argument I have worked from Richard Leonard's overly conservative 7,900nm which is 1,670nm more than necessary.
If you want to explain the discrepancy, first start with correct facts. That way you might find the discrepancy does not even exist!
Nothing in the posts up to this one disproves the ability of a Ju-390 to fly to New York with a bombload. It only advertises a poor grasp of the facts.
The claim incidentally arises from interrogations of two captured members of FernAufklarangsGruppe Nr.5 by US millitary intelligence.
Now if one were contemplating a highly top secret mission to drop an A-bomb on Manahatten, then one would not advertise the fact by keeping records of trial flights, nor for that matter, sharing the fact with all the members of FAGr5.
There was a Nazi nuclear project to build the bomb. Heisenberg was involved with the civil programme by Kaiser Wilhelm Gesellschaft to build a reactor... Not a bomb.
The Nazi A-bomb was under Dr Kurt Diebner for the Heerswaffenamt. He relied upon another project by Dr Paul Harteck to enrich uranium with gaseous centrifuges. The uranium came from mines at Jac-y-camor Czechoslovakia.
The second Ju-390 was flown to Uraguay at the end of the war and was seen there being dismantled by a Polish diplomat. You might want to contact author Nick Cook (author of Zero Point) and ask him if Igor Witowski was that man...
I provide a link to photos of the two Ju-390 prototypes.
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