Aircraft/Railway Combining Systems


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5 February 2011
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To be shown at the Paris Air Show shortly, but since the project has its own website, why not see it there? I think the EPFL might have something here (the infrastructure implications are especially interesting to me), though I'm sure others on this site are much more familiar with other unconventional passenger/ cargo configurations and can better draw those comparisons. Anyway, the following materials directly from EPFL's Clip-Air site:



Although air traffic has been increasing steadily by several percent per year, the concept of air transport has not seen any fundamental changes since the 1950s. “Airports are become ever more disconnected, waiting times are becoming longer, traffic levels are increasing, and overloads and delays are increasingly becoming the norm in air travel,” says Claudio Leonardi, in charge of the Clip-Air project.

Our needs in terms of mobility and the globalization of markets are not the only factors that are putting pressure on air transport. They are joined by energy-related constraints and environmental impacts. By the year 2020, the aviation industry has set the goal of cutting its CO2 emissions in half.

Rail transport's flexibility in air transport

How could this conundrum be unraveled? Clip-Air proposes a revolutionary air transport concept based on a flying wing that can carry mobile and interchangeable capsules. On the one hand, the Clip-Air plane is made up of a support structure including wings, engines, fuel and a cockpit. On the other hand, there is the load to be transported: passengers and freight.

The capsule is the equivalent to a conventional airplane’s fuselage, but without motors, without a cockpit, without fuel, without landing gear, or any of the other parts that usually make up a plane. The premise behind Clip-Air is to bring rail transport's flexibility to air transport and to make airports reach all the way into railway stations.
Principally the concept is not new, I think, just think of the Fairchild XC-120 Packplane. We had this theme
here,12049.msg117319.html#msg117319, or here,6263.0.html.
If a flying wing, often chosen because of its aerodynamic cleanness, is the best vehicle to be fitted with a fixed
landing and cargo pods, that probably would bring aerodynamic interferences with that wing, I don't know. But the
most important point here, is flexibility, which could only be achieved, if handling of the detached pods is possible
on nearly every airport. The website shows, that not only transport of cargo is envisaged, but of passengers, too,
probably by installing a system similar to the through coach of the railway. No need to leave your seat, when changing
the aircraft. Sounds good ! But AFAIK, the railway companies are more and more abandoning that system, as modern
trains are technical entities, to be divided only in the railway yard.
Reminds me AFRL CAT ( configurable air transport) concept from ca.2005
I'm not sure that this concept will find favour in the civilian world (maybe cargo but somehow, the passenger thing doesn't quite work for me) but I could see applications in the military world. Imagine the same platform [with a swift pod change] being able to do marine surveillance / ASW, launch stand-off weapons, cargo delivery, IFR, ISTAR etc etc. The pod shape would need to be standardised for trim and RCS reasons and maintaining the C/G (especially true with tailless platforms) may cause a few headscratches but it seems do-able.

What was that? "Clip-Air is 'go'!"? ;)
For military use, profitability has a slightly different meaning, than for civil use. If a tanker can stay longer
over the tanking area and/or deliver more fuel, an increase in fuel burn is acceptable. For a pax liner
today it's different, I think and for a civil freighter, too. Economy is the all important factor and using
such pods surely will result in a higher fuel consumption per seat, than in a conventional airliner.
Jemiba said:
For military use, profitability has a slightly different meaning, than for civil use. If a tanker can stay longer
over the tanking area and/or deliver more fuel, an increase in fuel burn is acceptable. For a pax liner
today it's different, I think and for a civil freighter, too. Economy is the all important factor and using
such pods surely will result in a higher fuel consumption per seat, than in a conventional airliner.
Probably but another factor in the economics is how long a passenger aircraft sits on the ground between flights. Reduction of the time to simple fueling, servicing, and connecting the pods would be an offsetting factor to fuel consumption. Part of the reason that airlines are less than "thrilled" with the blended-wing-body aircraft is the amount of time it would take to unload, clean and reload the aircraft for take-off. Another is the major changes such an aircraft would require for gates and terminals. While the "pods" would require some large changes to the way airport passengers services are run there are some important areas where such would be much better economically and organizationally than using BWB aircraft.

In either case airlines and freight-airlines would have to make some changes to incorperate either type of aircraft and they are of course reluctant to do so for something that may or may not be a "real" game changing technology. I'm suspecting that both the Pod and BWB is going to have to be used by the military first in order to give the concepts a track record to go by for civilian use. Unfortunatly it doens't seem that most military's will be able to afford to try both concepts any time soon and it may come down to simply which one gets in the door first.




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Good idea to use those pods directly as coaches, but ....
There's quite an important dimension for railway transport, the clearance diagram and the pods
would have to fit.
As shown below, the fuselage diameter of the B 737 wouldn't be usable, just something of
the size of the Embraer 190 would still fit. That, to my opinion, lessens the possible applications.
It may be a worthwhile service for a passenger to enter such a pod in the mid of his hometown in,
say, middle Europe, and leave it after a long distance journey to New Zealand, without going to the
airport by train, scurrying from the gate of the short-haul flight to the one for intercontinental flights
and so on. But such a flight in that tube ? Today it probably won't inspire most passengers, used to
wide body airliners.
Another point may be the necessity to carry galleys and toilets in every pax pod, probably more in the
sum, than otherwise in a single aircraft. Maybe good for the passengers, as it could decrease the wait
for a vacant toilet, but probably bad for profitability.

(pictures used from and )


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Great find my dear Pometablava,

and you can put their pictures here.


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This is my first post. I am a Product Design Engineering student at the Glasgow School of Art. I have been working for nearly a year on a future transportation concept for the year 2050. The first phase of my project has been called "The Horizon System"

Full information on the project can be found here:

Now I am in the midst of the second phase of the project as part of a group of three students. We are working on a new concept based around the topic of dynamic connections (changing between vehicles or transportation modes without stopping).

What are your thoughts on our work thus far (feasibility, passenger experience, technological limitations)? Can you point me in the direction of any similar concepts or relevant research? If you have a moment, we would also appreciate it if you participated in our survey on the air travel experience:
Welcome Mason and thanks for your input !
The Horizon System was briefly mentioned here, some thoughts you'll find in the older posts.
From the 'Manned verus unmanned airliners' thread:

Grey Havoc said:
An extreme take on 'unmanned':
Thank you for pointing me to that thread again ! I knew, that we had the Horizon System elsewhere.
Nevertheless, I'm not sure, that the following statement from the first link can be taken very seriously:
"The Horizon System is entirely electric. No fossil fuels are needed to keep the massive flying wing aloft"
No more black and brown coal,or gas (not to mention oil) power stations in 2050 ? I believe it, when
I see it ! ;)
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