Friday, January 18, 2008

Law enforcement blimps over Caracas

An article i read earlier this year on a new initiative in law enforcement in Venezuela could have interesting ramifications elsewhere especially in places like Iraq. According to this Reuters article the police in Caracas have bought a number of remotely controlled blimps to assist in law enforcement (not actually Zeppelins as the article states as this name implies rigid airship not a blimp but anyway). The unmanned airships will perform a monitoring role similar to as is performed by helicopters elsewhere but with a number of advantages. Helicopters are expensive to run and noisy, airships are much cheaper and an unmanned airship can remain on station for a much longer period because of the inherent advantage of lighter-than-air aircraft : they do not use up fuel to stay airborne. The airships will carry cameras to relay messages to the Police HQ.

HanGIS HAN1430 blimp

The idea of using blimps for law enforcement isn't new, an article in the 1981 Encyclopedia Britannica Yearbook of Science and the Future ("The Airship Returns" by Norman J. Mayer) mentioned the possibility of replacing helicopters with airships for some police operations. Much lower cost of operation and noise plus the ability for much longer endurance were cited as major advantages for these kinds of machines. A problem airships have suffered of course is that they are considered old fashioned.

Of course the major user of the airship was the Germans between 1900 and 1940, they used the airship for reconnaissance and bombing in the first world war and in the interwar period for passenger and cargo transport. The combat effectiveness of the airship was soon surpassed by the aeroplane however and indeed it can be seen that during WW1 airship design hardly evolved but aeroplane technology increased at an incredible rate (Stephenson 2004). The fact an airship was a huge slow moving bag of highly inflammable gas didn't help matters of course. Weather has also been an enemy of the airship with many lost due to storms .

The usage of helium instead of hydrogen and the non-rigid smaller blimp design saw airships see combat experience in the US up until 1961 (Gunston 1985), blimps providing an invaluable role in anti-submarine warfare and later for AEW. Again their endurance proving invaluable. However the US Navy considered the airship to be "archaic" and disbanded their fleet.

US Navy N Class Blimp

In the late 1970s and 1980s, with the blimp being largely reduced to the commercial Goodyear blimps, attention once again turned to the airship however, this time as an unmanned surveillance platform with incredible endurance. One project was Lockheed's Hi-Spot. This was a design for a high-altitude unmanned airship for surveillance and over the horizon targeting. It would have taken advantage of materials not available to Count Zeppelin such as kevlar and tedlar to give it a very strong yet light envelope. Computer control would be used to optimise the fuel use though solar power would also be possible to augment the finite fuel supply. Indeed a high altitude airship would be an excellent contender for solar power. Stated endurance for such a type was 100 days but maybe even longer.

Solar power would also be an option in warmer climes such as Iraq for example even if the blimp would operate at lower altitude. An unmanned surveillance blimp could have very long endurance if it could use solar power as much as possible, just using it's fuel supply for "action moments". The stated payload of a Caracas style blimp is 20KG so it would not be possible to arm such a blimp to counter any insurgency it discovered. However on station UCAVs like the MQ-9 Reaper could be vectored in and use targeting information from the blimp's sensors. A larger blimp might have the payload to carry armament but it would also become a very easy target (though this may be reduced by use of transparent material for the envelope perhaps). The Caracas blimp has a length of nearly 15m and a height of 5.5m so to carry a larger payload would require a fairly large blimp!

References :

"Venezuela launches Zeppelin to tackle rampant crime" by Christian Oliver (Reuters 2007)
"Zeppelins : German Airships 1900-1940" by Charles Stephenson (Osprey 2004)
"Warplanes of the future" by Bill Gunston (Salamander 1985)
"The Airship Returns" by Norman J. Mayer - 1981 Encyclopedia Britannica Yearbook of Science and the Future (Encyclopedia Britannica 1980)

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