Wraith601

I was kicking around some ideas earlier today and was wondering if the old concept of using airships for military applications was still sound.

Several years back I read an article in Proceedings about using AEGIS equipped blimps to provide a near permenant radar picket for surface ships. The ship would refuel via specialize dmasks raised from tankers or even Ticos. I suppose crew habitation could be an issue and there certainly are questions of vulnerability to attack, but the upside is there. Such a platform can loiter over or near a task force for extended periods, much longer than any one
E-2. Also, this would give ESGs and SAGs AWACS coverage without having carrier or land based planes available.

Comments or criticisms?

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Jimmy

They're effectively stationary. That's a huge limitation. Airships are frankly just slow. They can't defend themselves, even by running away. If their location isnt working out well for radar coverage, or due to weather, or any number of reasons, they can't reorient themselves fast enough to be of any value. Also, weather can REALLY wreak havoc on them. If there's any kind of winds, they're not taking off. And if they did, they're not steering themselves. So now you're stuck with a hugely expensive hanger queen that can only be flown on fairweather days.

I'm not a physics major or an engineer, but I'd expect there would be some development hangups in using a helium system to haul an AEGIS system in the air safely. I think we can all agree that hydrogen would not be the best option.

glyn

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glyn

Migman

What type payload could a Blimp carry? Certainly not an heavy AEGIS, leave alone a small whether radar? Unless it is really big.

glyn

The 'useful lift' of any airship is determined by the gas capacity. The bigger the craft (ignoring its un-gassed structure weight) the greater the gas capacity, the greater the payload that can be carried.
The US Navy employed AEW blimps, with the radar dishes inside the envelope. The ZPG-2W was 343' long, had a gas volume of 1,011,000 cubic feet of helium and had a crew of 24 with an endurance of 75 hours. The ZPG-3W was 404' long and had a gas volume of 1,516,300 cubic feet and a crew of 25 and could stay aloft for 90 hours. The rigid airship USS Macon (first flown in April 1933) had a useful lift of 160,644 lbs, a top speed of 72 knots, a crew of 60 and a range of 7,950 nautical miles.
I don't know the weight of an Aegis radar, or whether it could be made lighter so am unable to answer your question.

Dreadnought

Many people dont realize that during the "Doolittle Raid" preparation while USN Carriers Hornet CV8) and Enterprise (CV6) were underway at sea steaming towards Japan they met with an Airship namely L-8 over the Pacific to recieve urgently needed aircraft parts. An early example of shore to ship logistics and dropped them right on Hornets flight deck.

Thats a pretty good example of their use outside of other duties. A pretty accurate command of the airship as well because the carriers were sea heading towards Japan as quick as possible in order not to be detected before the launch of the raid.

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omon

Return of the Navy Blimps?
TCOM 32M aerostat
In the aftermath of World War 2, blimps and airships found themselves gradually phased out of the US military. That didn't begin to change until the 21st century (see April 2005, "USN, DARPA See Blimps & HULAs Rising"). The heavy-lift WALRUS project may have been canceled without explanation; but aerostat programs like JLENS cruise missile defense and its smaller RAID local surveillance derivative, and airships like the HAA/ISIS program, remain. The US Navy is also experimenting with aerostats for communications relay, surveillance, and radar overwatch functions - and this has become a formal program.

What's driving this interest? Four things. One is persistence, in an era where constant surveillance + rapid precision strike creates a formidable military asset. A second is cost, especially in an era of rising fuel prices. A recent US NAVSEA release offers figures that starkly illustrate the gap in surveillance cost per hour between an aerostat and planes or UAVs:

Land-based 71-meter aerostat: about $610/ hour
MQ-1 Predator MALE UAV: about $5,000/ hour
E-2C Hawkeye AWACS aircraft: about $18,000/ hour
RQ-4 Global Hawk HALE UAV: about $26,500/ hour

JLENS Concept
The third driver is ballooning bandwidth demands due to increased employment of UAVs and other systems with streaming video. This is a long-term trend that will demand very expensive satellites with long design/launch times - or cheaper patchwork solutions that can remain at altitude for long periods.

The fourth driver is the proliferation and increased lethality of cruise missiles. On land, the concern is the combination of cruise missiles and weapons of mass destruction. At sea, the concern is the increasing lethality of anti-ship cruise missiles, including supersonic varieties that place a premium on early detection in order to give defensive systems enough time.

Aerostats are not blimps, and need no pilot. These helium filled, multi-chambered balloons are winched up or down via a combined tether/power line; and can be deployed from trucks, land platforms, or a ship at sea. They can stay at-altitude and on station for weeks at a time, which makes them well-suited for providing over-the-horizon airborne radar, surveillance coverage, and/or communication relays for areas like ports, key sea lanes & straits, coastal areas, main transportation highways, national borders, or demilitarized zones.

Their multiple helium pockets and low differential pressure between the helium and the atmosphere also make them hard to kill, even if shot full of holes. The helium just escapes slowly, and the aerostat will still remain aloft for hours or even days. During one incident in Iraq, a small RAID aerostat came loose from its tether and the US Air Force barely managed to shoot it down before it drifted over the Iranian border.


E-2C Hawkeye
Aerostats will not replace naval surveillance aircraft. Their tethered nature creates substantial drag when moving at speed, and keeping them aloft at altitude becomes difficult in those circumstances. High winds and thunderstorms can ground them, in situations where aircraft could still fly. They also have rather large radar reflections, which can compromise task force stealth. Their offsetting advantages, however, may make them a critical naval supplement to be deployed over ports or staging areas; or from ships in or near "hot" zones like beachheads, or on picket in and near dangerous areas like the Persian Gulf, Straits of Malacca, Somali coast, et. al.


Radar: height matters.
Accordingly, the USA's NAVSEA and NAVAIR signed a memorandum of understanding on Oct. 28, 2006 to develop a sea-based 38-meter aerostat prototype with a weather hardened design that can carry up to 500 pounds of surveillance equipment. That's NAVAIR's area of expertise, and they will use a 32 meter aerostat they've been experimenting with as a base platform. The Navy also wants to develop this aerostat to accommodate a modular, interchangeable payload system that can offer radar, optronics, communications, or set combinations for maximum flexibility. That's NAVSEA's area of expertise.

The ultimate goal of the program is to develop a sea-based 71-meter, weather-hardened aerostat sensor platform, with larger interchangeable payload modules, capable of operating at an altitude of up to 15,000 feet. This would be conceptually similar to the land-based JLENS aerostats, which will provide cruise missile defense on land.
Return of the Navy Blimps? (defense acquisition, defence purchasing, military procurement)

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Wraith601

I was just thinking back on a scene from Stealth (I know), where there was an unmanned airship hovering the Indian Ocean serving as a tanker aircraft. Makes you think, in permissive enviroments where the enemy lacks weapons with the necessary altitude, airships could feasible in some support roles.

Jimmy

Having not seen the movie, that idea boggles my mind. I assume it was refueling helicopters or something?

Dreadnought

Hot air ballons were also used by Union forces during the Civil war as reconnisense for foward advance of troops and artiliary spotting in the America's. Note the name on the ballon itself. It would later become an aircraft carriers name in the USN.

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glyn

Dreadnought

Why yes Glyn it is the very one.

turtleairships

airships which are little more than glorified balloons (blimps, zeppelins) are NOT viable candidates for military applications, except in surveillance and telecommunications roles.

Virtually all airships continue to use archaic designs and technologies. The so called "hybrid airships", such as the P-791, the dynalifter, and the aeroscraft are ill suited for potential use as they require runways and are little more than large, helium filled airplanes; still heavier than air and susceptible to the same surface wind forces that plague airplanes in landings and take offs.

However it is possible to construct airships that can change aviation, and be of revolutionary benefit to militaries.

The greatest change that must take place, is to change the material out of which airships are constructed; to abandon the "envelope" of fabrics or laminates, and to build airships out of the same strong materials that airplanes are made of. Doing so will result in airships that can travel at high speeds (to 250mph), can hover, land or take off verticaly, land in water as well as land, employ new forms of power such as solar or alternative fuels, and able to carry immense payloads.

Airships have huge potential as OFFENSIVE military platforms. They can be STEALTHY. And, despite historic perceptions, airship have proven ability to "survive" in a hostile environment.

A stealthy airship cannot be found (hit) with a radar guided missile. Because engines are buried deep within a hull measuring several hundreds of feet in size, there is no discernable infra-red signature for heat seaking missiles to find. Striking, or blowing up an engine is moot; the airship floats in the air. Engines can be shut down completely and the airship will still fly.

Airships are extremely able to survive "ground fire". If an airship were to sit idly still for a full minute, while being shot at with a common 20mm gatling gun, pumping 6,000 rounds per minute into it....it would still fly. It might sustain 6,000 holes....but each would allow only 250 cubic feet of helium to escape each minute....and if an airship has multiple helium cells totaling over 8 MILLION cubic feet...then simple math shows that it would lose about 1.5 Million cubic feet per minute, or about 45 tons in lift. If an airship can carry 500 tons.....and is operated while carrying half that in water ballast that can be dumped....then, it has five minutes of flying time. At only 120mph, that puts it 10 miles away.

Of course, no airship would simply sit and let opposing forces shoot into it for a full minute, even if they were able to do so. And, as has been suggested; an airship can carry substantial DEFENSIVE weapons on board.

If you wish to know more about airships, please contact me. You might want to see my blog as well.