This story originally appeared on the defensenews.com website on May 1, 2012.

By William Matthews Defense News

Think back to 2008. Hundreds of U.S. troops were being killed and maimed each month by roadside bombs in Iraq and Afghanistan, and the Pentagon was pouring billions of dollars into technology to defeat the improvised explosive devices. The Army was buying mine-resistant, ambush-protected armored troop carriers by the tens of thousands, and Defense Secretary Robert Gates was browbeating his generals to field more surveillance unmanned aircraft.

The military launched ambitious efforts to build airships that would provide an unblinking eye over Afghanistan, and 2011 was supposed to be the year when the first efforts bore fruit. The Army and Air Force were vying to be first to fly football-field-length airships over Afghanistan, while a separate research team prepared to test the feasibility of a stratospheric airship.

Compared with standard unmanned planes, airships held the promise of staying aloft for days or weeks while carrying at least three times as much payload: infrared and high-definition optical video cameras, multiple radars, high-powered computers to process sensor data, and communications equipment to transmit the information on demand to users on the ground.

Plus, airship promoters promised they could do all that for a fraction of the cost of current unmanned aircraft.

“Everybody was chasing the Holy Grail of persistent surveillance, and airships promised to do it better and cheaper,” said a government analyst who is now examining airship programs. Cost, duplication and technical problems prompted some members of Congress to request a closer look.

The Defense Department has spent more than $1 billion on at least nine programs in recent years, yet the military owns just one working airship, a piloted Navy blimp called MZ-3A, which is used for research.

U.S. government watchdog agencies and independent engineers are beginning to ask tough questions because so far, the military doesn’t have much to show for its money:

• HALE-D, a $150 million “high-altitude, long-endurance demonstrator” built for the Army by Lockheed, crashed in July on its first flight, well before reaching its intended stratospheric altitude. The program is still on the books but has run out of money, the Army said.

• HiSentinel, a disposable Army airship designed to operate above 60,000 feet, has flown three times since 2005, but also has been plagued by problems. One flight was cut short when the airship sprang a leak; a second flight was aborted when the ship’s solar-powered propulsion system failed. HiSentinel, too, is out of money, and the shrinking defense budget makes future funding unlikely, the Army said.

• Blue Devil 2, an optionally piloted airship named for its “Blue Devil” multi-intelligence payload, is being canceled by the Air Force, effective in June, after multiple missed deadlines, technical setbacks and cost overruns.

• LEMV — or Long Endurance Multi-Intelligence Vehicle — an Army optionally piloted airship with an almost identical mission to Blue Devil 2’s, is struggling with missed deadlines and questions about its design. For months, government officials have been saying it is expected to fly soon, with the latest goal being April or May.

Three other high-altitude airship programs remain in early stages of development. They are the Navy’s balloonlike Star Light airship, which will have a detachable return vehicle; the Defense Advanced Research Projects Agency’s Integrated Sensor Is Structure, or ISIS, airship, whose radar will double as the ship’s airframe; and the Army’s High Altitude Shuttle System, which would have a detachable return vehicle and a disposable gas envelope.

Today, Blue Devil 2 (BD2) floats in a hangar in Elizabeth City, N.C., as work continues to complete construction of the 370-foot-long airship.

Started in early 2011 by 4-year-old aerospace company Mav6, BD2 was designed to fuse wide-area surveillance imagery with signals intelligence to rapidly spot and target bomb planters in Afghanistan. It would carry its 2,500-pound payload at about 20,000 feet and keep a round-the-clock watch over a 36-square-mile area for up to nine days at a time. Computers onboard would process the data collected by the airship’s sensors, rather than clogging bandwidth by transmitting vast volumes of raw data to the ground. Onboard data processing also was intended to permit Blue Devil 2 to operate with a smaller processing, exploitation and dissemination ground station.

The Joint Improvised Explosive Device Defeat Organization and the Pentagon’s ISR Task Force were keenly interested in the airship, which was supposed to arrive in Afghanistan by early this year.

But Mav6 said it encountered problems with suppliers. Overweight tail fins had to be redesigned and modified, causing delays. The most advanced camera had to be replaced because its proprietary data interface turned out to be incompatible with the Air Force distribution system. The avionics were more complicated than the vendor originally expected.

Mav6 has been urging the Air Force and Pentagon to push through the problems. Some technical issues were to be expected, the company said, because BD2 is the largest unmanned aircraft ever built and the largest airship hull built in 55 years. The technical troubles are far from unprecedented in scope for a groundbreaking intelligence project, it said. “For comparison, there is a space system that the [National Reconnaissance Office] director recently briefed that was 700 percent over timeline, and 300 percent over cost, but the DoD still pursued it,” retired Air Force Lt. Gen. David Deptula, now the CEO of Mav6, said by email.

The airship’s first flight was scheduled for October 2011 but has yet to occur. The deployment to Afghanistan has been canceled.

Funding for the program was conspicuously absent in February from the Air Force’s proposed 2013 research and development budget. After $66 million for 2011 and $63 million for 2012, there’s nothing for 2013.

Capt. Phillip Ventura, an Air Force spokesman, said in March that rising development costs, substantially higher sustainment costs and technical challenges prompted the Air Force to pull the plug on Blue Devil 2.

“The Air Force determined that these cost overruns, in the current fiscal environment, outweighed the potential benefits of a long-duration ISR capability. Consequently, the airship contract was definitized Jan. 31, and descoped to deliver only the airship by June 30,” Ventura said. The Air Force has not yet decided on what to do with the airship after it is delivered, he said.

Deptula and Mav6 have been pushing back hard, and the company now has at least two allies in Congress. Sens. Daniel Inouye, D-Hawaii, and Thad Cochran, R-Miss., reminded the Pentagon in a Feb. 14 letter that as recently as November 2010, the Air Force considered Blue Devil 2 as “urgently needed,” and that “the U.S. Central Command continues to maintain a requirement for this capability.” They added that “it would be a significant failure to stop work and not deploy this much needed platform to Afghanistan.”

Inouye and Cochran are chairman and vice chairman of the Senate Appropriations Committee.

Deptula called the cancellation of Blue Devil 2 “pound-foolish” arguing that the airship would provide 20 times the endurance of the fixed-wing aircraft that fly the Blue Devil 1 sensor suite.

Blue Devil 2 used a “conventional” airship design. That is, it’s a nonrigid, blimp-shaped “envelope” filled with helium to make it lighter than air. It has ducted propellers mounted on each side for forward thrust and one on the rear for steering.

While the Air Force wraps up BD2 in North Carolina, the Army continues building a substantially different airship to do essentially the same ISR mission.

The Army’s LEMV is a hybrid airship. At 302 feet, it’s shorter than BD2, and it looks a bit like two blimps pushed together side by side to make an especially wide, two-lobed airship. Although helium-filled, LEMV is not lighter than air. It’s designed to stay aloft using lift generated by its aerodynamic shape moving through the air. Four ducted propellers are intended to get LEMV airborne and keep it going at about 20 knots.

Like BD2, the unmanned LEMV is supposed to fly at 20,000 feet carrying 2,500 pounds of surveillance and communications equipment. But the LEMV is supposed to stay aloft for up to 21 days, compared with BD2’s nine. Whether it can is a matter of debate.

The $517 million LEMV is nearly a year behind schedule. Its first flight was originally targeted for July 2011.

Built by Northrop Grumman and British airship maker Hybrid Air Vehicles, the LEMV was inflated last fall and now sits in a hangar at Joint Base McGuire-Dix-Lakehurst in New Jersey. There, “the LEMV team is assembling the airship and integrating motors and electronics onto and into the vehicle,” officials from the U.S. Army Space and Missile Defense Command said in mid-March. The Huntsville, Ala.-based command manages the LEMV program.

“The first flight of the LEMV will occur when the airship has completed integration activities,” said the officials, who would respond only to questions delivered by email.

Plans call for the LEMV to fly first from McGuire-Dix-Lakehurst and be flown in piloted mode to Melbourne, Fla., where Northrop operates a large aircraft facility and has set up LEMV test equipment. From Melbourne, LEMV is to be flown across Florida for “government testing” at Eglin Air Force Base, the Army officials said.

After that comes a Joint Military Utility Assessment, which Army documents say is to be conducted in Afghanistan.

In Afghanistan, LEMV will have a flight duration between five and 17 days, depending on altitude, payload, mission and seasonal winds in the region, according to the Pentagon. Northrop Grumman and Space and Missile Defense Command have said LEMV could provide up to 21 days of persistent surveillance. Northrop also predicts that the LEMV will be “vastly cheaper” to operate than today’s unmanned ISR aircraft — Predators, Reapers and Gray Eagles.

Using a measurement called “payload duration,” which is the weight of its sensors multiplied by the amount of time the aircraft can remain aloft, LEMV could outperform the Army’s Gray Eagle by a factor of 80, according to the Congressional Budget Office (CBO), which examined the military’s airship programs last fall at the request of the Senate Armed Services Committee.

But the hybrid airship has its skeptics. Among them is Brandon Buerge, a Kansas-based aerospace engineer and former lead scientist for airship maker Guardian Flight Systems.

A hybrid airship the size of the LEMV, which must keep moving to stay airborne, will run out for fuel long before 21 days, Buerge said. He estimates that it can fly for about seven days. Others say four or five.

In a paper prepared for the American Institute of Aeronautics and Astronautics, Buerge contends that conventional lighter-than-air ships, not hybrids, which depend on aerodynamic lift, are better suited for long-endurance flights.

“The lifting body hybrid airship model was capable of carrying more than twice the fuel load of the similarly sized conventional ship,” he said. But hybrids burn through fuel fairly fast. “The much lower average fuel burn predicted for the conventional ship resulted in generally superior loitering performance,” Buerge wrote.

Peter Van Staagen also questions LEMV’s ability to stay aloft for three weeks. Vice president and chief technology officer of Information Systems Laboratories, a San Diego firm that focuses on ISR technologies among others, Van Staagen said, “Carrying that amount of payload and flying that duration at those altitudes — all of those are singularly difficult. Doing one is hard, doing two is very difficult, doing all three is impossible” with current technology.

Van Staagen estimates that LEMV can stay aloft for about five days. The Army’s 21-day mission? “That’s a real stretch,” he said. But the skeptics’ evaluations “have fallen on deaf ears,” and a half-billion dollars has been spent on the LEMV, he said.

When asked about flight duration doubts, Army officials responded with a prepared statement: “Flight durations will depend on each specific mission set and payloads, and cannot be discussed.”

But LEMV’s endurance is being examined outside the Army. Complaints filed through the Government Accountability Office’s FraudNET charge the Army with “waste, fraud, abuse and mismanagement of federal funds” for proceeding with LEMV and ignoring claims that the LEMV could not meet the 21-day flight goal.

GAO has begun examining the program, but a GAO official declined to provide details while the evaluation is underway.

CBO did not question whether LEMV could meet the 21-day goal but suggested that cargo hauling might be an apt use for hybrid airships. Their combination of helium and aerodynamic lift enables them to carry more than conventional airships, and being heavier than air makes them easier to handle on the ground during loading and unloading, CBO said.

Meanwhile, the Navy continues flying its own airship under the MZ-3A program. The 178-foot-long, lighter-than-air vehicle is a commercial airship that began flying in 2007 and remains the sole working U.S. military airship.

This one is manned. It can carry a pilot and nine passengers — or 2,500 pounds — and stay aloft for more than 12 hours. Its maximum altitude is 9,500 feet.

MZ-3A — it doesn’t have a catchy aircraft nickname — is “a flying research and test lab,” said Burt Race, the deputy director of the Navy’s airship systems engineering team.

Often, passenger seats are removed to make space for equipment to be tested, typically ISR sensors and communications gear.

This spring, the airship is testing C4ISR systems for the Army. In 2010, the 45-knots-per-hour airship was sent to New Orleans to serve as a reconnaissance platform for the Coast Guard at the height of the Deepwater Horizon oil well blowout.

With Coast Guard observers onboard, the airship flew over the Gulf of Mexico searching for oil slicks, directing oil skimmers to them and monitoring the impact of oil on wildlife, Race said. Unlike helicopters, the virtually silent airship does not spook animals, he said.

MZ-3A is owned by the Naval Research Laboratory and based at Patuxent River Naval Air Station, Md., but “we’re expeditionary,” Race said. “We can move just about anywhere in the country. We go where the business is.” Indeed, the airship keeps flying only as long as it has paying customers, he said.

“We are an efficient platform from a fuel standpoint,” and since it’s a simple machine compared to a conventional aircraft, the airship requires relatively little maintenance and achieves “a very high readiness rate,” Race said. “If you need to fly a lot [to test equipment], the airship may be very economical.”

MZ-3A won’t be going to war. “It’s strictly R&D, a test platform for testing sensors,” said Doug Abbotts, a spokesman at the Naval Air Systems Command center at Pax River.

Whether any of the other airships make it to war looks increasingly questionable since the Iraq War has ended and withdrawal from Afghanistan is scheduled for 2014.

“All the urgency and willingness to take the risk and spend the money [on airships] came out of Iraq and Afghanistan,” Buerge said. But as the wars wind down, the urgency is subsiding and the money is drying up.

A shift in the National Military Strategy also clouds the future for airships. The absence of air defenses and opposing air forces in Iraq and Afghanistan provided the “permissive” environment airships need to operate.

But the new strategy focuses on Asia and the Pacific, where permissive environments are less likely. “If you’re operating in someone else’s sovereign airspace, an airship is not ideal,” Buerge said.

The detailed article outlines the current military mission for airships as well as evaluates which type is best suited to fulfill the various military missions.

It is an excellent source of information as it provides a fair evaluation of merits of the Hybrid and Conventional modern airship. Please click on the link to download the PDF of the article.

Hybrid vs. Conventional Airship

While the design, materials and technologies that enable flight have changed a lot since the 1920’s, the fundamental laws of aerodynamics, economics and physics have not.

Success in the realm of airships lies in properly integrating the disciplines of aerodynamics, economics and physics – resulting in a modern airship that applies modern design, materials and technologies and integrates them into a proven Concept of Flight Operations like that which was proven and perfected in the first three decades of the 20^th century.

Low cost efficient aerial transportation is a key economic and military enabling mechanism that promises to deliver a highly efficient and cost effective solution a multitude of  21^st century military and economic problems. And the solutions exist today.

A correctly designed and built modern airship will be structurally sound and can scale safely to the sizes needed to be economical. It will operate at or near neutral buoyancy at all times, and carry heavy payloads long distances or for extended periods of time at very low cost.

There has been considerable confusion related to hybrid airships, which are heavier than air vehicles like airplanes, which require the burning of fuel in order to fly. Hybrid airships are in fact not lighter than air vehicles, which operate at or near neutral buoyancy at all times in order to be fuel efficient and cost effective.

For purposes of further clarification, the basic principles of correct lighter than air (LTA) design, construction and operation are as follows:

1.     For an airship to perform properly it MUST operate at or near neutral buoyancy at all times: The fundamental principles that govern lighter than air flight and consequently, correct airship design, construction and operation, are very similar in principle to those which underlie the correct design, construction and operation of a submarine. The main difference is the medium in which they operate, a submarine obviously operating in water and the airship operating in the air. The bottom line: For an airship to carry heavy loads for long periods of time with low fuel burn at low cost relative to other more familiar forms of air transport, an airship MUST operate at or near neutral buoyancy at all times.

2.     Scalability: Airship lift is volumetric, NOT aerodynamic. Every time the volume of lifting gas is doubled, the gross lift of the vehicle is tripled.  This means that airships must be built in large sizes in order to carry heavy or outsized loads efficiently and cost effectively. The key is to design and build an airship that is large enough to be efficient and cost effective but is also structurally safe and can scale to sizes where economics really make sense. The idea is to use helium to do the lifting and to use propulsion exclusively to propel the airship, NOT to generate lift.  Therefore, a correctly designed and built modern airship will be defined to balance volume and buoyant lift, sized to maximum operational payload and shaped to achieve best aerodynamic and economic efficiency.

3.     Airships are low speed structures. For an airship to perform well and be economically efficient, the optimal airship operating speed is at or below the stall speed of an aircraft wing. Attempts to design or fly airships over 100 M.P.H. fail to correctly distinguish, understand or isolate the inherent characteristics of lighter than air that are desirable and decouple them from those characteristics of lighter than air that are suboptimal or undesirable.

4.     Economics – Airships are simple, low speed structures. Simplicity means low cost. Increased efficiency (save time, increase capability, do more with less cost, fuel burn, environmental impact, etc.) and transformational operating capability and low cost economics are the reasons to build a modern airship. The way desirable economics and tremendous operating efficiencies are generated with an airship is by designing a lighter than air vehicle that operates according to the following principles: A. Uses aerostatic lift (helium) to lift the vehicle and payload, B. Uses propulsion exclusively to propel and maneuver the air vehicle and payload, NOT to generate lift. C. Fly safely by designing and building an airship that will exceed modern FAA flight safety requirements and standards by broad positive margins (and not be susceptible to weather and break apart in flight like large rigid airships of the past) and D. Design an airship in such a way that it can operate from remote areas with minimal infrastructure, making large ground crews unnecessary for landing and take off and E. design the airship in such a way that the vehicle has positive full axis control at low airspeeds (airspeeds under 3 knots).

The high fineness ratio multi mission airship design is the result of extensive research and development and fundamentally advances the state of the art in modern airship design. This design is non rigid and divides a long cigar-shaped airship into sections or segments that act in a manner similar to a large shock absorber. This is similar in concept to an aircraft wing that is designed to flex under loads rather than remain rigid.

Extensive research has shown that a modern long fineness ratio airship is substantially more load and cost efficient than equivalent payload shorter blimp-like airships. However, history has shown that all past long fineness ratio rigid airships had inherent structural inadequacies, many resulting in catastrophic failures. This series of airships has correctly analyzed and isolated the operational and structural inadequacies of the past era.  Therefore, the high fineness ratio multi mission airship design advances the current state-of-the-art for ultra-large pressure airships. The overall result is a fineness ratio in excess of 8:1 which provides a minimal cross section and capital and operating cost relative to payload capability.

Therefore, the modular, High Fineness Ratio Multi Mission Airship is tailored and optimized to the mission and is defined to balance volume and buoyant lift, sized to maximum operational payload and shaped to achieve best aerodynamic and economic efficiency.

In summary, I will leave you with two thoughts: 1. According to John Adams, “Facts are stubborn things”, which when applied to airships is intended to mean that while the materials and technologies have changed, the fundamental principles of lighter than air flight have not, and 2. Competition is what inspires creativity, innovation and excellence, improves performance and lowers costs. A level playing field and open and fair competition has been sorely lacking in military contracting for airships to this point.

In 1917 the German Zeppelin L.59 attempted to fly 50 tons of military supplies from Germany to German troops in what was then German East Africa (Now Burundi, Rwanda and Tanzania) under the command of Gen. Paul von Lettow – Vorbeck. The flight covered a distance of 4,200 miles, which is equal in distance to a nonstop flight from Germany to San Francisco, California using the great circle route.
Built in 1923, the US Navy airship Shenandoah regularly used less than 3,000 hp while transporting 53,500 lb of payload up to 5,000 miles at cruise speeds of about 70 mph.
In 1928 the German airship Graf Zeppelin was the first vehicle to circumnavigate the globe by air. It flew nonstop legs eastward from Germany to Japan, which was a nonstop distance of 6,988 miles, and then from Tokyo to San Francisco, which was a nonstop distance of 5998 miles.
Despite the vastly inferior design, materials and technology of the era, mission profiles covering strategic and transcontinental distances with very heavy payloads were routinely flown by airships in the first three decades of the 20th century. Airships of this era repeatedly exhibited operational capabilities that could not be duplicated by airplanes 40 years later.

Our nation’s vital strategic interests rely upon open and unrestricted access to each of the three global commons, the sea, the air, and cyberspace for commercial and military purposes. These global commons are the lifelines of commerce and prosperity in the modern world. Affordable and unrestricted access to each of the global commons for commercial and military purposes is the key to the continued prosperity and stability of the modern interconnected global system. A properly designed, constructed and deployed airship will provide a platform to maintain and expand access to the global commons mentioned above.

A high fineness ratio cargo airship is a modern advanced design airship that uses some of the best design characteristics from the past history of dirigibles such as having a long fineness ratio for providing best aerodynamic/buoyancy efficiencies versus payload. The inherent core design feature of the Cargo Airship System (CAS) is a long slender cigar like airship that can provide net payload capability from 20 tons to over 500 tons depending upon overall proportions (size).

CAS is designed to have a minimum of five individual cylindrical buoyant sections. Each individual section interfaces and is connected to each other to complete a large airship with outstanding overall structural integrity. This configuration is capable of transporting greater than or equal to 40,000 pounds of flexible payload (vehicles, pallets, litters, personnel, etc.) at altitudes greater than or equal to 10,000 feet mean sea level (MSL) with a cruise speed greater than or equal to 80 knots and have a range of at least 1,000 nautical miles.

The interface of each section is designed to achieve maximum safety and full control over all structural forces encountered by the airship, including maximum forces of tension, compression, and torsion as encountered by a large-long streamlined style of airship. Overall structural integrity is in excess of 90 f.p.s gust loading, whereas all historical long finesse and rigid dirigibles were structurally limited to 17 f.p.s maximum gust loads. Modern pressure shorter finesse ratio airships such as blimps meet modern approvals of at least a minimum of 35 f.p.s cost load criteria, (a jumbo jet minimum gust load criteria is 65f.p.s.). The, structurally sound, long fineness ratio ‘CAS’ presents a major breakthrough for operational transport efficiencies of payloads with adequate structural integrity in all weather conditions.