no !
same way as in a submarine ! (for not to be detected by sonar)

main engines stopped but control by electroengine for the rudders,elevators…
silent engine without flameexhaust = still stealthy :))

and to make the trip to n.y. the zep did not have to fly over britain. (see atlasmaps 1940-1945 item)

when i ever go to friedrichshafen(D) i will talk about this matter.
i hope they do show me some documents…

only a detail but….

at night and flying high the zeppelin could turn off all the engines
so it could fly in and sneak over new york almost completly invisible and without any sound !

i doubt that the USA had the right nightfighters on the ready
to intercept such a stealthy (yes !! already in that timeperiode) bombplatform.

from the zeppelins point of observation they had a very good
overview on the target because of the citylights a.o. lightsources while the zeppelin was completly without any lights on.

after the boms were dropped the zeppelin became less heavy and therefor could also go faster after making a u turn and
getting out before the surprise attack had come in the
defensive role by the usa.

i think some important detail is forgotten here !

facts:
the germans did had a platform to bomb new york already
in…1929.
and they could do it in a non-stop flight.

yes ! the z e p p e l i n !

payload:
replace any 4 average passengers for 1 bomb of 250 Kilo or 2 bombs of 125 Kilo and you have a deadly load onboard.
(keep in mind max.passengers allowed on each flight and.. deduct the weight of their luggage because bombs do not need extra weight for their luggage!)

strategic weapon:
1941/1942 version would be an updated one in safety (non-explodic hull paint),gas,reliability and capable for a non-stop
return flight europa-usa-europa

and about the german a-bomb…
the usa was lucky the belgian king sold them the uranium
for their 1st atomic bomb because he “owned” the belgian kongo,and therefor also the mines.
just think what could have happened if that king had sold the uranium to the germans in return for a heavy load of german bars of gold…

in the past a/c have been “exported” out of irak
example:

hawker aircraft ltd
kingston-on-thames,england
FB11
S/N N41H65G803 SEA FURY

was among a bunch of ex-iraki sea fury a/c sold to an american “a/c hunter”
connected with the confederated air force harlingen,texas (now moved to midland,tx)

restored by
tom’s aeroplane service live oak,fla

owned and flown by
tom crevasse & john williams

registered as
N19SF

painted in the colours
NAVY 121

a/c could not pull up again after a mock dogfight with an ME108 at harlingen,tx
and was complety destroyed on impact.

====>

so it is either:

a)let the irakis in charge resulting in the a/c cannibalised for
parts to be sold on the black market and the restants rotting
away in sun,wind and vandals action.

or

b)get them out of irak a.s.a.p.