The August 17, 2022 Lunch & Learn program was presented by Calvary's own Mr. Gene Jend.

by on August 17, 2022

Hail and Lightning and Birds, Oh My!
Lunch & Learn — August 17, 2022

The “Learn” part of “Lunch & Learn” for August was presented by Calvary member Mr. Gene Jend. Gene recently retired from Rolls-Royce after 35 years in the Experimental Test Department working with jet aircraft engines.

Mr. Jend said not only does each assembled engine undergo rigorous testing before being put into service, but every component and sub-assembly is thoroughly tested. Vibration is a key concern for oil and fuel lines enveloping the engine assembly. Testing exposes areas that require potential leak problems.

Gene explained ever since Ben Fraklin made his kite/key connection of lightning and electric current, we have experienced the drastic results of electrical storms. Burned structures reveal the need for a means to channel the electric charge and lightning rods were developed. A decades long argument for pointed tip rods versus rounded tip rods seems to be leaning towards the slightly rounded design.

Forty-five people die each year from lightning strikes with Florida averaging one person injured each week. Aircraft industry records indicate that every aircraft is hit by lightning twice a year. These hits are usually at the rounded nose, travel the length of the plane, and exit in the area of the tail surface. Construction of the airplane is such that passengers likely will not be aware of a lightning hit. The pilot may sense some anomaly with the instruments which may require a decision to continue or land.

Gene detailed some incidents which resulted in notable crashes. In 1963 a lightning strike caused a mid-air explosion which gave impetus for better shielding and surge suppression on aircraft. A 1994 American Eagle flight crashed in northern Indiana with no survivors. A lengthy holding pattern at O’Hare Airport during inclement weather subjected the aircraft to ice buildup on the wings resulting in the crash. Improvements were made for flexible boots on the leading edge of the wing that permitted shedding of accumulated ice.

Every aircraft crash is a unique set of circumstances, and the National Transportation Safety Board is charged to thoroughly examine all conditions and issue directives to strive to eliminate future mishaps.

The 1989 crash of a DC-10 was attributed to the Auxiliary Power Unit (APU) which is a small engine in the rear of the plane. This engine supplies electrical power to the aircraft while on the ground and in flight. As this engine failed in flight it caused collateral damage to major aircraft systems.

Gene described some of the failure test required by the Federal Aviation Administration (FAA). He showed a video of blade destruction testing where an explosive charge is detonated on an operating engine. The goal is to keep any rotating, loose parts from penetrating the engine housing. Test is also done with water ingestion, hail ingestion and bird strikes.

He explained the bird strike test for a mid-size engine required a five-pound duck. The test facility will have a number of live ducks that are maintained for use. Since the FAA requirement requires a five-pound duck, underweight ducks are fed, and overweight ducks are rationed. The ducks are weighed prior to testing so they meet FAA requirements. They are humanely killed with CO2 gas prior to testing.

The most recent bird strike event was the Hudson River water landing. Two Canadian geese were ingested in each of the two engines with disastrous results. The skill of the pilots and the design of the aircraft resulted in the survival of all personnel (except the geese).

Alternate fuels are being considered. Chicken fat and beef tallow can be burned in jet engines. Propeller engines with electric power generated by an APU unit are also an option.

Gene closed by stating that testing is done with very tight security and personnel involved are pledged to secrecy.

Submitted by Chris Karamasines (AKA???)

Keywords: lunch, learn, engine, aircraft, jet