How Flying Humvees Will Work

Before you can understand how a flying Humvee works, you need to understand what a Humvee is. Humvee is the common spelling for off-road, armored, truck-based military vehicles, but the technical spelling is HMMWV, which stands for High Mobility Multi-purpose Wheeled Vehicle. The first Humvees were built in 1983 by American General. The military was looking for "a family of versatile, technologically advanced, cross-country vehicles capable of performing both combat and combat-support roles. The basic chassis was to be capable of being modified into a number of variants. It was also to be diesel-powered, consistent with the Army's desire to use diesel fuel throughout its tactical vehicle fleet, and it was to have an automatic transmission" [source: American General].

Today's Humvees don't stray far from those requirements. Compared to the first Humvees, today's Humvees have bigger engines, better towing and payload capacities and better reliability. There also more heavily armored. As improved as today's Humvees are, however, they can't live up to the requirements the Pentagon has for flying Humvees, namely that they be able to fly (for a start), drive on roads, carry personnel and cover 250 nautical miles (287.7 miles or 463 kilometers) in flight while carrying 1,000 pounds (453.6 kilograms) of payload with a maximum altitude of 10,000 feet (3,048 meters). DARPA also wants it to be "somewhat green" [source: Wired]. That will be tough for a vehicle that only gets about 14 miles per gallon (5.6 kilometers per liter). So, while we call these flying Humvees, the end product will have little in common with the ground-only Humvees the military uses today.

Given that developing a flying Humvee will be expensive, time consuming and risky, you may wonder why DAPRA wants to create one at all. The U.S. Military does a good job of ground patrols with conventional Humvees, and helicopters do a good job patrolling airspace, engaging in aerial combat and providing air support for ground troops.

Safety is the main reason the Pentagon is developing flying Humvees. The conflicts that today's military engages in don't follow traditional rules of battlefield and combat. Instead, the military has to contend with loosely-organized urban fighters who blend in with the civilian population. That makes ordering airstrikes from a helicopter difficult. The risk of hurting civilians is high.

At the same time, ground troops in a conventional Humvee can easily become the victims of improvised explosive devices (IEDs) and roadside bombs. In some cases, hostile forces use IEDs and roadside bombs to not only injure American troops, but to also lure more troops to the area, since troops that are hit with IEDs will call for help. Since IEDs are on the ground and can be triggered by contact, a patrol vehicle that can fly might keep troops safe from them, or allow them to evacuate safely and quickly if they're attacked. Flying Humvees would also allow troops to get to an area where they're needed quickly and safely. Also, if ground troops needed intelligence on an enemy's position, rather than calling for helicopter support, which would take time and allow enemies to regroup or hide, they could just get airborne and see for themselves where to concentrate their fire.

Of course, a vehicle that can keep troops safe, drive on the ground and fly is a tough thing to engineer. Keep reading to see just how a flying Humvee will work.

The project name for the flying Humvee is Transformer, and some of the capabilities of the flying Humvee sound like they came out of the Transformer universe.

The most startling thing about the flying Humvee is the pilot: There won't be one. DARPA specifies that the flying Humvee be robotic. The Transformer will have wings that fold out of the roof and a foldable center rotor as well. A ductable fan on the back provides forward propulsion. Fuel for the Transformer will be stored in the wings.

Three main contractors are working on the flying Humvee: Rocketdyne, Lockheed Martin and AAI Corp. Rocketdyne will create the engines and already makes jet and transport plane engines for the Airforce. Lockheed Martin is the largest defense contractor in the country. The main design comes from AAI.

Right now, designs are in the first phases. AAI has a $3 million contract from DARPA to cover feasibility studies, wing studies, propulsion, materials and flight controls. The first prototypes aren't expected until 2013 -- and those prototypes are expected to be partial prototypes. The full development phase is expected to cost $9 million. That's a pretty steep total for just the first phase of the project, which is has a total budget of $40 million.

Retractable wings, robot pilot, ability to fly 250 nautical miles (287.7 miles/463 kilometers) and drive on the ground like any other military vehicle. It sounds like science fiction, but if DARPA has its way, flying Humvees will be hitting war zones soon.