Last August, I had the unique, and quite wonderful, opportunity to pilot a North American B-25 “Mitchell” Bomber of World War II vintage.
While those of us in the aerospace field probably think of aircraft from 80 years ago as simple, when I began studying the manuals and procedures to prepare for the flight, I realized that there were plenty of operating systems and design choices that went into creating these medium-range bombers. That said, piloting the aircraft made me think about the contrast to today’s advanced electronics, artificial intelligence, cutting-edge automation, lightweight composites and fly-by-wire controls.
There are lessons that can be drawn from this contrast.
One of them is that complexity comes with a big trade-off: the inability to react quickly and make large numbers of aircraft. The United States produced just over 2,000 total aircraft in 1939, but in 1942, the first full year of the war for the United States, production soared to 47,000 aircraft. Then to over 85,000 in 1943, according to the National WWII Museum. Our allies built another 50,000, and our adversaries built tens of thousands. Regardless of whether the aircraft were fighters, bombers or transports, each was designed for available materials, for manufacturing by moderately skilled workers, and to be operated and flown by quickly trained crews. Maintenance personnel had only the simplest tools, yet they were able to quickly return aircraft to service. The aircraft designs were straightforward and geared to accomplish specific mission objectives. Flight controls were cables. Flight instruments were air-driven. A couple of hydraulic pumps with shuttle valves operated the landing gear and flaps. Radios had vacuum tubes inside.
Flash forward to the present era, and the contrast is stark. On average, roughly 200 fighter aircraft (including those for foreign delivery) and approximately 700 transport aircraft are produced per year in the United States. Fewer fighters but about the same number of transports are produced in Europe. These aircraft are more capable, for sure, but also much more complex than their WWII counterparts. Their designs count on materials that didn’t exist a couple of decades ago. Assembly line workers require a year or more of training beyond high school. Flight crews undergo years of training before ever seeing the flight deck of a transport or fighter aircraft. Avionics are so integrated into the aircraft that multiple layers of redundancy are necessary, because the aircraft won’t fly without the avionics. Aircraft and engine maintenance is complicated, with some components taking months or years to repair.
In terms of performance, these aircraft are astounding compared to those of 80 years ago. But we have to ask ourselves: Are the aircraft, their avionics and their maintenance equipment becoming so exquisite that we soon won’t be able to afford the planes in the numbers we need?
We should wonder what Kelly Johnson, the legendary World War II engineer and Lockheed Skunk Works founder, would say. In his day, Johnson touted the KISS principle: Keep it simple, stupid. He told his designers to aim for “results cheaper, sooner,” and apply “common sense to tough problems,” according to a biographical memoir written by his former colleague, Ben Rich. “If it works, don’t fix it.”
While Johnson was talking about aircraft design, the KISS principle also tells us that simple aircraft can perform significant operations. In 1987, a 19-year-old West German teenager flew a single-engine Cessna 500 miles (750 km) through Soviet air defenses and landed at the gates of the Kremlin in Moscow’s Red Square. More recently, the war in Ukraine has repeatedly demonstrated that small drones are inexpensive yet effective weapon delivery systems. In the Middle East, Hamas began the Oct. 7, 2023, terror attack in part with commandos flying powered paragliders, according to reporting in the Haaretz newspaper. Like the drones in Ukraine, the gliders literally flew under the radar.
Judging by expenditures, KISS has been forgotten. The U.S. Air Force obligated nearly $17 billion for new combat aircraft in 2024, the Navy obligated another $15 billion for the Navy and Marines, and the Army obligated about $5 billion, according to USASpending.gov. This does not include the expense of training crews to operate and maintain the current fleets.
A place we could adapt quickly is in the realm of unoccupied aircraft. To date, the focus has been on complex systems so that each vehicle can accomplish a broad array of missions. An alternative would be to manufacture simpler, less expensive units in large quantities, each kind designed for a specialized mission goal. Strategists would count on overwhelming numbers to ensure completion of the mission. For that reason, these aircraft are sometimes labeled “attritable,” but that’s not quite the same as expendable. Some might make it back after striking targets to be reused. This basic concept of operations is not entirely new. It was employed by the Allies in World War II with piloted aircraft, including B-25s like the one I piloted. Dispatching lots of bombers ensured that some reached their targets and made it home.
The loss of life was, sadly, tremendous. Today, the Pentagon could be ready to employ the strategy with multitudes of small inexpensive mission-specific unoccupied aircraft. Kelly Johnson, I believe, would be pleased with the simplicity of this idea.
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