Airships (blimps and Rigids known as Zepplins) played imortant roles during world War I and World War II.
In world War I they performed not only observation roles, but even were the first truly Long Range Bombers. The Bombing of London (though technically a Failure) proved the feasibility of strategic bombing and defintely proved the need to ground based fighters and better Air Defenses.
"The Birth of Strategic Bombing was in WWI when German Zeppelins began raiding London from bases in occupied Belgium. Small attacks against England were carried out early in the war, but by October 1915, "squadron-size" raids by numerous Zeppelins had begun, always at night and in the dark of the moon. Early in September 1916, a British fighter shot down an airship, and three weeks later, two Zeppelins attempting to attack London were also destroyed. Although Zeppelin performance was gradually improved, so were British balloons, and improved anti-aircraft defences and heavy losses continued. After a disastrous raid on August 5, 1918, the Germans practically discontinued Zeppelin warfare. There were 159 Zeppelin attacks against England in WWI, resulting in the death of 557 people, primarily civilians, and damages of $7,500,000." (
http://www.century-of-flight.net/Aviation%20history/airplane%20at%20war/upload2/bombing%20by%20Zeppelin%20airships.htm)
Despite the discontinued use in front line units due to their inherent susceptibility, in World War two they performed roles such as Coastal Recon, Search and Rescue, Anti-Submarine Warfare. Two Main classes of Airships were operated by the US Navy. These were the K and M class LTA's (lighter Than Airships).
The K Class:
"In World War II K-ships made 55,900 operational flights of over 550,000 hours. During that war 89,000 surface ships were escorted by K-ships. Not a single one of these surface ships was lost to enemy submarines. The submarines feared the presence of the airship in spite of the fact that there is no public record of an airship ever sinking an enemy submarine" (
http://battleblimps.com/k-ships.html)
"After the attack on Pearl Harbor in 1941, the Navy asked the U.S. Congress for authorization to purchase an increased number of airships. By June 1942, Congress had authorized the construction of 200 airships, and during the war, Goodyear built a total of 168. At its production peak, the company was turning out 11 airships monthly.
The later K series airships were slightly larger and had a capacity of 416,000 to 425,000 cubic feet (11,780 to 12,035 cubic meters). They were 253 feet (76 meters) long, and 60 feet (18 meters) in diameter, and were powered by two 425-horsepower (317-kilowatt) engines that gave a top speed of 50 miles per hour (80 kilometers per hour). They were not fast, but unlike an airplane that could remain airborne for only a few hours, a K-ship could stay aloft for 60 hours." (
http://www.centennialofflight.gov/essay/Lighter_than_air/Airships_in_WWII/LTA10.htm)
Sources also state the K class carried four depth Charges and a single machine gun (.50 Calibur) along with Magnetic Anomoly Detction equipment (MAD) and Radar.
M Class:
"The Goodyear Aircraft Company of Akron, Ohio built the M-class blimp for the US Navy as the follow-on to the K-class anti-submarine warfare blimp used during World War II. It was a significantly larger airship. Four airships, designated M-1 through M-4, were delivered in early 1944. Operations of K-ships in tropical regions had shown a need for a blimp with greater volume to offset the loss of lift due to high ambient temperatures.
A contract was awarded to the Goodyear Aircraft Company for the prototype M-class blimp on August 16, 1943. This contract was followed by another contract on September 11, 1943 for 21 M-class blimps. These airships were given the Navy designation of ZNP-M, (Z = lighter-than-air; N = non-rigid; P = patrol; M = type/class.) However, on November 22, 1943, the quantity of blimps was reduced to four. These were delivered to the Navy in February, March, and April 1944.
General characteristics
Crew: 10-14
Length: 302 ft 0 in (92.07 m)
Diameter: 69 ft 6 in (21.19 m)
Height: 92 ft 6 in (28.20 m)
Volume: 647,000 ft3 (18,320 m3)
Useful lift: 10,000 lb (4,356 kg)
Powerplant: 2 × Pratt & Whitney R-1340-AN-2 radials, 550 hp (410 kW) each
Performance
Maximum speed: 80 mph (128 km/h)
Cruise speed: 58 mph (93 km/h)
Endurance: 50 hours 30 min
Armament
1 × .50 M2 machine gun
8 × 350 lb (159 kg) Mark 47 depth charges"
(wikipedia.org, Article Mclass Airships, accessed 2012)
Not only Would the implementation of Airships be a minor improvement to the World War II arena's, but they would be a huge boost to World War I Arena where Airshgips actually saw the most use during any given war period.