Afterburner: Keeping the Flame Burning at NASA Dryden
Jet engines are extremely sophisticated, exactingly engineered marvels of modern ingenuity.
The most powerful propulsion engines next to rockets, jet engines span the realm of power from small hobby engines that produce 50 pounds of thrust, to giant turbofans that produce over 100,000 pounds of thrust. The largest of these, General Electric's GE90-115B engine, can generate 123,000 pounds of static thrust. That engine is one of the types used to power Boeing's 777 airliner.
Enrique "Henry" Hernandez knows the marvels of turbojet engines well. As the chief of NASA Dryden Flight Research Center's jet engine shop, Hernandez came to NASA after working with jet engine manufacturer General Electric for a number of years. He actually set up the shop at NASA Dryden in 1994, primarily to support Dryden's growing F-18 fleet, which is powered by General Electric F-404-400 jet engines.
"We do practically all the maintenance work on our F-404 engines here, except for rotor balancing," Hernandez relates. "We take these engines totally apart when necessary to inspect and replace parts, so we're a full-service operation."
Taking apart and putting back together such powerful devices that require exacting precision adjustments can be tedious for Hernandez's group. Two civil servants and two contractors staff the shop.
"It's not uncommon for us to have an engine partially assembled, then have to disassemble it and start over because the numbers aren't correct," Hernandez says, noting that measurements of hundredths of an inch can at any moment reveal a misalignment earlier in the process.
The work can sometimes be challenging and stressful, but the team knows how to keep a good balance.
"We work hard here, but we like to have fun, too. Our Bar-B-Qs are legendary," Hernandez says.
Shop mechanic Aaron Rumsey also enjoys his job, and takes his love of mechanics home.
"I like to work on cars, motorcycles and quads; I love this stuff." Rumsey says.
The engines for which Rumsey is responsible at work are just a little more powerful than what he tinkers with at home.
A typical V6 family car engine like that of a Toyota Camry produces about 268 horsepower. If you want to go fast on the ground, a Lamborghini Murielago puts out about 640 horsepower for a top speed of 211 mph.
Time to strap-in: a General Electric F-404 jet engine, like those used in NASA Dryden's F-18 aircraft, generates 6,400 horsepower, or 16,000 pounds of thrust as jet and rocket engine power is measured! The twin-engine F-18 tops-out at Mach 1.8, or approximately 1,369 mph.
The jet shop doesn't maintain all the center's engines on the same level as the F-404s. The shop provides accessory maintenance and borescoping for engines like the Pratt & Whitney JT9D-7J that power NASA's SOFIA 747, or the CFM56-2C engines that power the DC-8 flying laboratory. When major engine work is required, these engines are shipped to the manufacturer for repair or overhaul according to support contract agreements. This holds true for the center's F-15 research aircraft and others as well.
The shop works regularly with other organizations at Edwards Air Force Base and elsewhere.
"We work well with our industry and military partners, and we like free stuff," Hernandez says.
Some of the "free" stuff Hernandez and his shop have received through such partnerships includes F-404 engines and spare parts from the U.S. Air Force's F-117 stealth fighter program, which ended in 2008.
NASA Dryden research pilots keep kick'n the tires and light'n the afterburner fires in the skies above Southern California's Mojave Desert, thanks in no small part to Henry and his small team of jet mechanics who are keeping the flame burning.
NASA Dryden Public Affairs