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AlliedSignal Aerospace Propulsion Engines produces propulsion engines for business class executive jets and auxiliary power engines for both commercial full•size airlines and business jets. As cinematographer for ASAC, it is my responsibility to provide high speed motion analysis of the catastrophic testing sequences that the engines must pass in order to receive FAA certification. This paper will outline and explain several of the tests that propulsion engines must undergo to receive FAA certification. The test parameters and setups concerning photography will be explained herein. Within the testing profile we have established our cameras of choice are Redlake hi-cams and 10-cams. These have been used exclusively because they have demonstrated the durability to withstand the harsh environments at our San Tan test facility 35 miles southeast of Phoenix. In addition to the Redlake compliment we also make use of 2500W HMI type illumination. Our test regime is structured so that the illumination for the tests permit the test to be conducted at any time of the day and regardless of weather. Testing programs at AlliedSignal have evolved from early years where seldom more than two or three cameras were used to photograph an event. Today, with the commitment to engine development time tables being so strict, we have substantially increased the photographic coverage of an engine involved in catastrophic testing like foreign object ingestion or full blade out testing. On a blade-out test, wherein a single blade is, with a small charge, explosively released at a Max-Power setting, 16 cameras are utilized to provide redundant coverage's of flight inlet areas, aircraft mounts, accessory components, exhaust behavior, and then for primary overview of the test. Optical considerations on hazardous testing require some level of risk to cameras on some positions of the testing, like blade-out events, hi-cams are at times located within 1-2 feet of the engine itself. Blast shields with lens cutouts have been used to protect cameras, but shooting in close, and lighting in close has proved challenging. The HMI lighting used is generally oriented to the flight inlet area. On a blade-out event or similar severe test, accessory and mounts are critical subjects so they are examined in a 3k to 7k frame rate. We have utilized 2k Tungsten light sources to provide illumination in these tight areas. Our lenses utilized range from 50mm lens for inlet perspectives, 25mm for overview perspective, and 10mm to 15mm lenses for extreme tight areas underneath the engine. The only real difficulty encountered on under-engine cameras has been with the effect of oil/fuel misting on lenses. on a blade-out test, and the majority of other extreme testing, the preferred frame rate is from 7K PPS to 9K PPS. Our efforts to coordinate cameras and events have proved to be very challenging so we have integrated a camera control that will initiate the cameras from a firing computer, wait for a specific % frame rate signal from the hi-cam shutter pulse circuit, and then trigger the blade charge once the desired number of cameras are at speed. This effectively has given us a fail-safe condition where the control of the event still remains secure in the event of any technical anomalies. Once the predetermined sampled cameras convey the required number at speed the firing control then commits the event to explosive blade separation. In addition to the cameras controlled by the sequencer there are cameras both high speed and real time that are initiated manually. The blade out test is by far the most severe of the testing segments and the high speed coverage directly reflects the critical aspects of the test. In addition to the blade out test, high speed photography utilizing cameras from 500 PPS us to 7K PPS are also used on the Ice Slab Ingestion, Hail Ingestion, and finally the Bird Ingestion segment. Included here are test plans that will detail the specific criteria necessary to perform each of these tests starting with the Fan Blade Containment Test, followed by the Ice and Hail Ingestion Test, and concluded by the 1.5 pound Bird Ingestion Test.
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