The Mitsubishi Regional Jet has gotten off to a strong start in 2018. The first major test of the year was for high altitude testing, an important benchmark that gauges whether engines, auxiliary power and other important aircraft systems can perform well in thin, low density air.
In 2017, the MRJ development program made significant strides. A re-organization at Mitsubishi Aircraft Corporation offices earlier last year strengthened program teamwork, which led to notable testing progress and a successful debut at the Paris Air Show.
While the MRJ continues on its path toward type certification, we take a look back at the important milestones the program has achieved in 2017.
It’s a sunny and hot July afternoon in Eastern Washington, and Kenji Okimoto is racing down the runway of Grant County International Airport. Okimoto, a vice president at Mitsubishi Aircraft Corporation America who runs operations support at Moses Lake Flight Test Center, is looking to position himself near the right runway so he can take a group of guests to observe today’s take-off of the Mitsubishi Regional Jet (MRJ). Air traffic control switched the runway due to a change in the wind conditions.
At the Moses Lake Flight Test Center in Washington, FTA-4 underwent cargo smoke testing between April 7 and April 22, 2017. To set up the test, engineers at Moses Lake installed a smoke machine and flexible hoses inside the cabin, along with lights, smoke detectors, and cameras to monitor real-time smoke generation. During the test, the hoses that were routed under the floor of the aircraft pushed smoke towards the test areas in the cargo compartment and the amount of smoke was controlled using the video cameras.
On Monday June 19, CNN Aviation editor and self-proclaimed AvGeek, Jon Ostrower reported on the debut of the Mitsubishi Regional Jet at the Paris Air Show. In the 90-second CNN Money segment and accompanying story titled “Sharp-nosed Japanese jetliner could be game changer for U.S. flyers.”
During the flight load survey tests, more than 250 pressure sensors and strain gauges affixed to the aircraft measured the maximum loads on its external surfaces and components. Throughout the test flights, the crew maneuvered the aircraft to reach specified G-loads, maximum rudder deflection, and roll and side slip thresholds as our engineers monitored the data and Japanese aviation authorities witnessed and approved the test via the telemetry room.
At McKinley Climatic Laboratory on Eglin Air Force Base in Florida, FTA-4 underwent extreme temperature tests between February 28 and March 17, 2017. After initial set up, temperatures sunk down to -40° C for five full days of extreme cold testing. Following this, the testing team removed their winter coats and swapped in their t-shirts, and ratcheted the heat up to 50° C for several more test days. Among other systems, the test and data gathered is used to validate the performance of the Environmental Control System (ECS). “Pull-Up” and “Pull-Down” tests, which begin in a cold or hot soaked condition, measured the ability of the system to control the cabin and flight deck to a comfortable temperature within a specified time.
Flying the aircraft at varying altitudes and speeds beyond maximum operation limits, the high-speed flutter test demonstrated sufficient margin on the normal operating envelope of the MRJ. Testing for flutter – a phenomenon that occurs when aerodynamic forces cause rapid self-excited destructive vibration – required a heavily instrumented aircraft operated by well-trained crew that was monitored by engineering specialists on the ground.
In February and March 2017, Flight Test Aircraft 4 (FTA-4) performed initial natural icing tests based out of the Rockford International Airport in Illinois. This was the first off-site test campaign to collect data in these conditions.
Tests performed by a team of global specialists using dedicated flight test instrumentation obtained valuable data to analyze the airframe ice accretion and Ice Protection Systems performance. Guided by a meteorologist on the ground, FTA-4 flew through clouds with specific moisture content, water droplet size and temperature resulting in varied icing conditions to understand how the aircraft would perform and eliminate ice on the leading edge of the wings and engines during flight.
As a prerequisite to the type certification lightning test later this year, we completed an internal simulated lightning strike assessment on Flight Test Aircraft 5 (FTA-5) in December 2016 in Nagoya, Japan. To simulate lightning strikes, we applied a low electrical current to the aircraft, which produces a magnetic field around certain areas of the aircraft, such as the ports, engines and the edges of the empennage on the tail.