Project Description

C-140 JetStar
A C-140 JetStar was flown by NASA's Dryden Flight Research Center from 1964 to 1989 on a variety of of projects applicable to civilian aircraft. Built by Lockheed, the aircraft arrived at Dryden in May 1963, and carried tail number 814.

Dryden, in co-operation with the Lewis Research Center, used the JetStar to investigate the acoustic characteristics of a series of subscale advanced design propellors in the early eighties. These propellors were designed to rotate at a tip speed faster than the speed of sound. They are, in effect, a "swept back wing" version of a propellor.

The JetStar was modified with the installation of an air turbine drive system. The drive motor, with a 24 inch test propellor, was mounted in a pylon atop the JetStar. The JetStar was equipped with an array of 28 microphones flush-mounted in the fuselage of the aircraft beneath the propellor. Microphones mounted on the wings and on accompanying chase aircraft provided far-field acoustic data.

In the 1960s, the same JetStar was equipped with an electronic variable stability flight control system. Called then a General Purpose Airborne Simulator (GPAS), the aircraft could duplicate the flight characteristics of a wide variety of advanced aircraft and was used for supersonic transport and general aviation research, and as a training and support system for Space Shuttle Approach and Landing Tests at Dryden in 1977.

In the 1970's the JetStar was part of cooperative industry-government program that attempted to establish noise characteristics and determine the effectiveness of alternate landing approach procedures in reducing community noise levels. Besides the NASA/Lockheed Jetstar, other aircraft involved in the tests were a Rockwell Saberliner, a Grumman Gulfstream II, a Gates Lear Jet, and a Beech-Hawker 125. Each of the aircraft flew four different types of landing approaches over a microphone array, and were evaluated and compared to the most recent noise level limits proposed by the Federal Aviation Agency (FAA).

In 1985, the JetStar's wings were modified with suction and spray devices in a laminar (smooth) air flow program to study ways of improving the flow of air over the wings of airliners. The program also studied ways of reducing the collection of ice and insects on airliner wings. Test articles mounted on each wing incorporated insect and ice protection with laminar flow control. The test arcticle mounted on the right wing used suction through approximately 1 million 0.0025-inch diameter holes in the titanium skin to maintain laminar flown on the upper surface of the article. In addition to a shield, a propylene glycol methyl ether/water mixture spray was used for insect protection.