Classic Video Looks at the Certification Process for the 727 and 747
When Boeing built the revolutionary 727 and 747, it had to develop equally revolutionary ways to test and certify the advanced aircraft. Boeing faced a number of challenges along the way. Spray patterns of the 727’s tires could have quenched the outboard engines. A redesign was necessary to prevent potential flameouts. The 747 also faced a number of challenges. One was a surprising difficulty when starting engines in windy conditions. The turbofan engines would overheat if there was a tailwind during starting. The engineers had to devise a way to overcome these challenges…and they did.
This video is a Boeing documentary was released way back in 1990. It documents the test programs of the legendary 727 and 747 aircraft. If you can get past the cheesy music, it’s a treasure trove of rare airplane facts for Avgeeks.
About the 727
The loud, smokey Boeing 727 is a mid size, narrow body, three engine jet aircraft. It can carry up to 189 passengers. Between 1962 and 1984, 1,832 Boeing 727 jets were manufactured. All of them had three Pratt & Whitney JT8D engines, located below the T-shaped tail. The 727 was not exactly the perfect jet. In fact, airport noise regulations have led to all remaining 727s being fitted with “hush kits”, much to the disappointment of plane watchers who love loud noises. The Boeing 727 was built with three engines. Also included in its design was an emergency exit door at the back of the plane that also served a dual purpose as a tailstand to prevent tipping during loading. The 727 is now in limited service for cargo and private transport.
About the 747
The Boeing 747 is a wide body commercial jet aircraft, often referred to as a Jumbo Jet, or Queen of the Skies. It has four engines, and can accommodate as many as 400 passengers. The Boeing 747 was introduced in 1970 to Pan Am Airways. Its primary users today are British Airways, Korean Air, Lufthansa, China Airlines and various cargo operators. As of July 31st of 2016, there have been 1,523 Boeing 747 jets manufactured.