A Brief History of the Burlham Safety Post

by Thomas Clayton Mayo

November 19th, 1999

While employed by General Dynamics Defense Systems in Pittsfield, Massachusetts, I became involved in the development of the General Dynamics DeadEye 40/50 self-stabilized machine gun mount for the 0.50 caliber Browning Machine Gun (BMG) and the Mk 19 Grenade Launcher. The Browning Machine Gun was invented in 1912 by Browning, and has remained unchanged since. It is still widely used in the military today. The Mk 19 Grenade Launcher is an automatic weapon that rapidly fires 16 ounce high explosive rounds which detonate on impact. The action of the Mk 19 is spring-based vs. reciprocating, so when early versions of the gun were transported on rough terrain with the weapon pointed into the sky, it occasionally discharged into the air, sometimes with fatal results. The barrel of the Mk 19 was designed short so that the round would exit the weapon at the maximum velocity. When the weapon was first demonstrated to the military, the inspecting officers were dissatisfied with the stubby appearance of the weapon and ordered extra barrel length added to give it a longer appearance. Further, an unneeded flash suppressor was added.

For the DeadEye project, which incidentally I named after a cartoon hornet which appeared on an alcohol beverage which was a favorite at the time, General Dynamics was teamed with a company called Military Systems Group in Nashville, Tennessee. This company was formed by a man named Pony Maples and his wife. Mr. Maples was over 70 years old at the time of the project, if I remember properly, and had been involved in many exploits such as the underwater recovery of nuclear test rounds in the Pacific atolls and monitoring Soviet satellite transmissions in the Arctic Circle with the CIA. Mr. Maplesí company was involved in the design and manufacture of mounts for light and heavy machine guns for boats, tanks, light vehicles, and helicopters. Many of his customers were South American governments trying to clean up the drug trafficking in their countries. Others were Middle Eastern governments who purchased the mounts to dispatch suicide boat bombers while in unfriendly waters. The team effort was assembled by Mr. Maples and Joe Doktor from General Dynamics. Joe Smolenski was the primary technical contributor. He was responsible for early portions of the mechanical and drive motor electronics and addition acted as the General Dynamics 0.50 caliber firing expert, substituting for Charles Runyon of MSG when he was on travel. I was responsible for implementing the two-axis motor control loop in a Motorola HC16 microcontroller, some early mechanical design, and in addition, I was the alternate Mk 19 firing expert.

The testing of the design took place in Murfreesboro, Tennessee, home of the Barrett Rifle Company. Barrett makes the M82A1A 0.50 caliber Special Applications Scope Rifle used by U.S. Marine Corps snipers among others. Barrett had a combination test range and goat farm in the farmlands outside Nashville. For the purposes of the testing the DeadEye stabilization system, we mounted it to the roof of a Humvee and drove several runs on the test range. As it was a "clean" range, no incendiary rounds were allowed, so we fired practice rounds for the Mk 19---large slugs of aluminum. The original DeadEye consisted of a short post with a rotating chassis containing the slew drive motor, electronics, and microcontroller. In the front of this chassis, there was a canister which could carry 300 0.50 caliber rounds or 85 Mk 19 rounds. Atop the rotating chassis was the machine gun cradle. On the cradle were mounted a firing solenoid, two accelerometers, and an electrically powered piston for weapon elevation.

After successfully completing three test firing trips to Nashville, we decided to take the Humvee to a military show at the Military Police school in Alabama. We towed the Humvee on a trailer behind Mr. Maplesí Toyota 4-Runner and even saw some snow on this trip. The show was fascinating. There was a remote control Humvee, an up-armored Humvee (they usually have fiberglass panels which do nothing to prevent errant rounds from puncturing the passengers), and a competing stabilization system made by Kollmorgen in Northampton, Massachusetts. Inside the facility there were demonstrations of different types of armor, tasers, different kinds of ammunition, uniforms, rations, radios, computers, and a remote control lawn tractor with a camera and robot arms for bomb disposal or hazardous location inspection. It was very interesting to be dressed in coveralls one day assembling the mount onto the Humvee in the motor pool and then change into a suit and tie to speak with the military personnel the next.

During these trips, both to perform test firing in Murfreesboro and to the show in Alabama, Mr. Maples, or Pony as he allowed, would tell us war history facts, having been so heavily involved with the military throughout his long career. One story, and I hesitate to even use the word story because they were all true, was about the ten-day egg. This account is about a delicacy that is eaten in the Pacific Islands. The natives take a seagull egg and bury it in the sand for a requisite number of days before cracking it open and eating it. It is eaten raw and spoiled and the longer the wait apparently the higher quality of the delicacy. I wish I could remember the details of where and when this was done, but it is certainly true as all of Ponyís stories are.

A second story, and the one after which this essay is titled, concerns the Burlham Safety Post (BSP). During World War I, when aircraft were first being introduced as a military asset, safety provisions were at a minimum. Seat belts were not commonly used due to the extra effort required to release oneself from the cockpit in the event of a crash landing. As you can imagine, fires frequently broke out after crashes, and to be caught in a burning plane made of cloth and wood meant certain death. Equally perilous was pilots falling from their aircraft when banking or diving, however, so something needed to be conceived to satisfy both needs. A British Ace named Henry Burlham invented a device which was extremely simple and useful. The Burlham Safety Post enjoyed wide popularity among British pilots. It consisted of a well-polished brass post mounted in the center of the seat which the pilot would sit on. To be clear, the post was inserted through a flap in the pilotís uniform and into his rear end. When performing a maneuver that could throw the pilot from the aircraft, he would tighten his muscles and be able to maintain not only his position in the seat, but also excellent control of the plane. The device was eventually phased out as quick-release harnesses were invented. But many pilots from the era recollected the Burlham Safety Post fondly.