June 13, 2009
Qantas and QantasLink have led the field in a new air safety enhancement. Bird strikes and related damage have been significantly reduced across the entire Qantas and QantasLink B737 and DHC8 fleet by a new and relatively low cost initiative.
The bird strike problem was highlighted when an Airbus A320 passenger jet was forced to ‘splash down’ in New York’s Hudson River after it encountered a flock of Canadian geese heading for a winter in Florida.
Both its engines failed, but a skilful emergency ditching saved all the passengers and crew. However the event highlighted the ever-present hazard that bird strikes pose to commercial passenger aircraft.
It turns out that Qantas was already on the case. The event had highlighted the point that bird strikes are not limited to the lower airspace around airfields; they can occur at altitudes of up to 10,000 feet or even higher, especially when long-distance migratory birds are involved.
It is now known that damage from smaller birds such as swallows, previously thought to be harmless, can inflict undetectable damage to turbine blades because they are small enough to pass through engine compressors to the “hot end.” The scorched remains of their dense bones become embedded in small cooling airflow passages on the turbine blades, causing localised overheating and eventual shortening of blade life, resulting in expensive unscheduled overhauls.
Qantas has now trialled and adopted a relatively low-cost electronic device on its domestic aircraft fleet that significantly reduces the frequency of bird strikes. Pulselite is an electronic switching system that causes an aircraft’s landing lights to pulse 45 times per minute like the flashing lights on emergency vehicles. The technology in effect, better announces an aircraft’s approach, thereby giving a bird more time to get out of the way.
The Qantas evaluation collected data sets from “host” B737 aircraft in the 400 (Classic) and 800 (New Generation – NG) fleets that had the Pulselite system installed. It then compared outcomes against the remaining non-host aircraft in each respective fleet over a minimum period of 12 months operational service. In some statistics from the trials the number of birdstrikes per 1,000 departures was reduced by up to 66%.
Before the trials were completed the statistics were so convincing that the decision was made to equip the entire Qantas B737 fleet with Pulselite. The system is now fully operational in Australasia with a number of other operators, including QantasLink’s Dash 8 100/200/300/Q400 Fleets).
During 2002 – 2003, Sunstate Airlines conducted a 12-month evaluation of the system in five DHC8-300 aircraft. The results, compared to the remaining eight non-Pulselite equipped DHC8 aircraft, clearly demonstrated lamp life improvement of 300%+, wildlife strike reduction of approximately 50% and birdstrike reductions of approximately 35%.
Singapore Flying College (LR-45 Fleet), RAAF VIP SQD 34 (Challenger 604 fleet), National Jet (DHC8), Tenix Corp (DHC8), Gippsland Aeronautics (GA8 Airvan) as well as a number of helicopter and private aircraft operators in Australia also now have the system installed.
Airlines such as Air Nelson (Air Zealand), Horizon Airline (part of the Alaska Air Group), Air Pacific, Air Vanuatu, Jet Connect (Qantas New Zealand) are also customers.
Advantages now acknowledged for the system are enhanced conspicuity to other pilots and to air traffic controllers, and increased landing light bulb life because each lamp operates approximately 150° cooler than normal, diminishing the effects of vibration on the bulb filament, reduced unscheduled engine maintenance/overhaul costs boosting return on investment, and enhanced safety and schedule integrity, as well as improved core safety values.
The system’s control units are a compact set of electrical components that will apply regulated pulsing power to the specified external lights instead of the normal steady “on” position, the only visible difference is an additional selector switch position on the landing light switches, and the system is easily integrated into the aircraft’s existing external lighting and traffic collision and avoidance (TCAS) systems which can automatically activate the system and connected external lighting upon receipt of a TCAS traffic advisory if required.
Pulselite is not normally restricted by aircraft minimum equipment lists, unless required by the operator, and is available in units for general aviation aircraft, large capacity 28 volt D.C. units for larger aircraft, and 115 volt AC. units for military and transport aircraft.
Unit cost ranges from US$295.00 for an average GA type aircraft up to US$4,595.00 for an aircraft in the Boeing B737 category.
The smallest unit weighs 0.28 kgs, has capacity for two lights at 125 Watts, or 1 Light at 250 Watts. The largest units weigh 0.88 kg and can operate on 28 VDC Switching Voltage, or 115VAC Switching Voltage and operate up to 6 circuits of 600 Watts per circuit.
The system is now standard on the high-end Grumman Gulfstream, and available as an option on 85% of all new aircraft in the USA corporate aviation community. The system is mandated in the aerial wildfire fighting community in the USA and now also for firebombing aircraft and rotorcraft in many parts of Australia. It is also mandated in the USA for helicopter tour operators in heavily congested areas such as Grand Canyon, Hawaii and New York etc to make them more conspicuous in the ‘see and avoid’ environments.