New York - London Air-Ship Traffic: A fancy project
( May be called “NYLAST” for short.)
Created by Carl O. Nordling, Sweden
This is a rough sketch of a project for a
pleasant form of passenger traffic between Europe and America. The readers of this home page
are invited to criticize the ideas put forward so far, and to contribute with
improvements based on expert knowledge in each of the various fields that are
involved in the project. Such contributions will be received through Internet
at carl.o.nordling@swipnet.se. Contributions
that I find interesting will be displayed on this home page together with the
name and country of the contributor.
A new mode of trans-Atlantic communication
rests on the following prerequisites:
1. Timetable
and comfort. If you cannot spend the best part of a week on a ship cruise,
you cannot cross the Atlantic especially
comfortably. Consequently, a great degree of comfort and an attractive timetable are essential for the ability to
compete with the present means of communication (i.e. airplane and ocean liner).
Therefore ample board and sleeping accommodation should be provided, but
passengers should not have to spend more than one working-day on the journey. To
meet these requirements, passengers should be offered to dine after boarding, a
six- to eight-hour sleep, a day with access to various restaurants and entertainments
and possibilities to do paper/computer-work, another eight-hour sleep and
finally breakfast before landing. This seems to require start on day one at 6
p.m. and landing on day three at 9
a.m., or something thereabout. Considering the five
hours’ time difference between Western Europe and Eastern
America it means 34 hours for the eastward flight and 44 hours for
the westward one.
2. Places
of destination and speed. In order to meet a maximum demand, the terminals
should be placed as near the greatest metropolises on each side as possible, tentatively
London and New York – provided that the airships can be
made to travel fast enough to keep the forenamed timetable. Since there is usually a west wind on the North Atlantic, a speed of 150 km per hour would prove to
be quite sufficient for the eastward journey along the 5,600 km long great circle
between the two cities. A following wind of just over four meters per second
would be enough for the airship to reach the 164.7 km/h virtual (over-land)
speed needed in order to cover the distance in 34 hours. The westward journey
is more complicated because it means either sailing rather straight against the
wind or choosing a longer route. The straight route is possible only at headwinds
below 6.3 m/sec. The choice of route must be done particularly for every
journey in view of the topical wind situation. The route via Iceland, Greenland and Labrador
will probably prove to be the most expedient in the great majority of the
flights. With e.g. 100 km
light fair wind, 2,900 km
light crosswind and 3,000 km headwind of 7 m/sec the airship would also need an
inherent speed of 150 km/h
for a 44 hour journey. A rather normal route seems to be from London
via the Hebrides, touching the coasts of Iceland
and Greenland right on to the Labrador Sea, all with more or less fair winds,
then via Labrador, St. Lawrence River and Vermont
to New York,
all with crosswind. Although this route measures some 6,300 km it may often
require less than 150 km/h
inherent speed and still make it in 44 hours. Considering exceptional
circumstances, the engines designed for an enduring cruising speed of 150 km/h should have a
capacity of temporarily producing a speed of, let us say, 170 km/h.
3. Passenger
capacity. An airship capable to travel economically at a speed of 150 km/h must be rather
big. Economic reasons speak for a passenger capacity of at least 500
passengers. The lack of experience of such whoppers speak
in the opposite direction. Let us therefore calculate with an average number of
500 paying passengers plus 50 tons of paying cargo. Ample accommodation for the
passengers would require e.g. 250 cabins adaptable for one or two passengers
and 50 cabins adaptable for up to four passengers. In case all the cabins
happen (extraordinarily) to be filled up to top capacity there would be 700
passengers and the loading capacity would be reduced to 30 tons
4. Power.
The type of power plant and propulsion fuel must be chosen with regard to the
weight of the fuel in the first place. The lightest fuel is of course hydrogen,
which may be stored on board both as compressed (in heavy containers) or as a
complement to the main lifting gas (supposed to be helium). Airship Hindenburg
ran on a mixture of propane and hydrogen with a density equalling that of the air.
An alternative to consider may be oil to be used during the initial and middle
parts of the journey and hydrogen gas to be used during the last part. This
system would cause the airship successively to climb up to about 2,000 m (thereby reducing
air resistance) in order to descend when burning the hydrogen. This would
permit a flight without loss of ballast or (the expensive) helium. This
solution depends on the possibility of constructing high efficiency motors
workable on both oil and hydrogen.
5. Fuel
and motors. The weight and the
efficiency of the motors is another important element. In case oil forms the
major part of the propulsion fuel, the weight and efficiency of the motors must
be chosen so as to minimize the combined weight of the motors and the fuel needed
for a 44 hour journey. I have seen somewhere that Stirling
motors weighing 1.6 kg/hp with 40 - 45 percent efficiency can be constructed.
In case that can be verified, it would prove a good solution. If, however some
kind of gas is used as propulsion fuel, the choice of motor type becomes more
complicated. A very efficient motor will minimize the volume of the propulsion
gas needed, but if the motor is very heavy, it will need more lifting gas
instead. The more gas that is needed for whatever purpose, the larger the ship
and the higher the air resistance. The cost of the fuel cannot be ignored
either.
6. Propulsion.
All the large airships built so far have been driven by propellers applied to
gondolas mounted beneath the bulk of the ship and containing the motors. I am
not sure that this is the best solution, given the technology of today. Another
alternative that should be considered is a system of air ducts through the bulk
from stem to stem with fans (turbines) in the middle. Such a solution, with “12
ducted fan vectorable thrusters fore and aft” has been proposed by Quantum
Aerostatics (www.quantumaerostatics.com).
It would of course change the aerodynamic characteristics of the ship
completely and need careful calculation.
7. Shape.
In order to minimize air resistance the bulk of the airship should be
streamlined and contain both the lifting gas and almost everything else, i.e.
passenger cabins, restaurants, cargo compartment, crew, fuel, ballast, life
rafts, etc. The cockpit protruding underneath (and possibly the propelling
gondolas rigged on their frames) should be the only exception. Rudders and
tail-planes should be dispensed with, to be displaced by directional thrusters
fore and aft.
8. Materials.
Since the big airships of the 1930’es were built, many new materials have been introduced.
New or conventional material for the gas bags is an open question, but there
are most certainly better light metal alloys for the hull of the ship than
those available in the 1930’s. We also have new materials like carbon fibre, Kevlar,
nylon and plastics for a number of details in the design, such as stays and
external coating.
9. Hull. Today the carrying structure can probably be
made lighter than what was possible in the 1930’s thanks to Buckminster Fuller’s
invention of the framework shell used for his “geodesic dome”. The same
principle should be adapted for streamline shape. A preliminary estimate of the
dimensions required results in a length of about 370 m, and diameter about 67 m, which would mean a total
volume of about 870,000 m3
(cubic meters).
10.
Interior fitting-up. Passenger comfort is essential for the whole project.
Therefore all passenger cabins should have windows (necessarily facing
obliquely down). This would require two decks for the cabins with their corridors, placed along the sides of the
ship. All the
restaurants, cafés, lounges, cinemas, dance floors, casinos, reading rooms,
etc. should be on full decks below.
11. Places for terminals.
Have you anything to suggest? In New York the “Flushing Airport”
on Long Island looks expedient. Google Earth
shows it as a triangular field on College Point not looking like an airfield at
all, but it seems to be vacant. In London
I have found Wormwood Scrubs (Hammersmith/Willesden) and Parliament Hill
(Hampstead). Could any of these be available? The terminals should of course be
placed as near the central quarters as possible, and preferably in the
directions of destiny (i.e. NE of central New York
and NW of central London.)
12. Mooring. Since I know
nothing about present-day solutions of this rather crucial problem, I must
refer once again to the proposals of Quantum Aerostatics that can be studied at
(www.quantumaerostatics.com).
13. Prevention of ice accretion.
If possible, the accretion of ice on the hull should be forestalled. If this
cannot be achieved, some means of removing the ice must be installed on the
airships. So far, I have no idea about how to solve this problem.