Rule the roost – mitigating the threat of bird strikes12 September 2014
Bird strikes are a dangerous event for aircraft, and regulations brought in by the CAA making the reporting of their occurrence mandatory have served to outline the scale of the issue. Here, Andy Baxter, former leader of the bird-strike avoidance team at the Food and Environment Research Agency, explains what airport operators can do to decrease the likelihood of incidents and how the future of strike risk management lies in predictive technology.
Following the highly publicised emergency landing of a Malaysia Airlines flight travelling into Kathmandu, just days after the disappearance of Flight MH370, the Federal Aviation Administration (FAA) released statistics indicating that the number of bird strikes reported in the US quadrupled between 1990 and 2012, rising from 1,851 to 10,726. These strikes caused 4,538 precautionary landings, 1,788 aborted take-offs and 372 engine shutdowns.
Worldwide, a similar trend has been noticed; since the Civil Aviation Authority (CAA) mandated bird-strike reporting in 2004, there has been a significant increase in the total number of reported bird strikes.
But for Andy Baxter, former leader of the bird-strike avoidance team at the UK-based Food and Environment Research Agency (FERA), it's a misconception that bird strikes have increased.
"There's no problem with increasing numbers, it's the species being struck that is the issue," he says. "If you're getting large, flocking birds being hit, that's far more problematic."
In North America, the number of large birds - including cormorants, bald eagles and Canada geese - has increased, with conservation and urbanisation cited as the two main factors contributing to the rise in bird strikes.
When it comes to urbanisation, Baxter cites Canada geese in the UK as an example: "Their numbers are growing in urban parklands," he says. "It's an area of caution where bird strikes and aspects of risk management should be looked at."
Information is key - In 2004, bird-strike reporting was made mandatory in the UK. However, CAA data shows that 40% of reported bird strikes contain no bird species information. In May 2010, the organisation launched a campaign for those who report bird strikes to the CAA, encouraging them to identify the bird species involved in a strike.
Increasing the knowledge base of such events will allow airport operators to assess and mitigate this risk, and Baxter maintains progress has been made in assessing the risk from bird strikes.
"A dead bird on the airfield can be identified," he says. "But a few feather remains require specialist expertise and techniques like microscopic feather analysis.
"Additionally, identifying which species are on your airfield is about ensuring the airport operators and the personnel are able to identify different species."
The UK's CAA acknowledges the importance of bird identification to help airfield personnel put together habitat-management programmes and implement dispersal techniques, but Baxter believes the ideal solution for making airports' habitats as unattractive as possible for birds is monoculture grass of 150-200mm.
"You don't want birds to feel secure on an airfield," he says. "Swampy and rutted areas must be avoided, there should be no food resources in the grass and hangars must also be made as unattractive as possible."
Beyond that, it's a bird-deterrent exercise, which involves airport staff driving around using pyrotechnics, distress calls and shooting, if necessary.
"It's about people putting more effort in than the birds; that's the real answer," Baxter emphasises.
Once an airport has the bird-management basics, Baxter has no objections to operators using the latest technology. "It's far better to secure the basics - habitat, bird-control training and equipment - before introducing newfangled technology," he says.
The early bird
However, when it comes to preventing bird strikes, it is prediction technology that has the most potential, according to Baxter.
"Airports need to calculate where the birds are and where they're coming from," he says. "Predicting when they're going to come is next."
There are several options, but bird-detection radars are perhaps the most valuable. FERA owns and operates the only two mobile bird-detecting radars for civilian use in the UK, which detect and record moving targets, and operate continuously over a period of days, weeks or months.
"In certain circumstances they're excellent, but in others they're not as suitable," Baxter acknowledges. "It's something for airports to decide."
Detection technology can be expensive, but compared with the cost of a catastrophic incident, they are highly practical.
"The Hudson River is the example that always gets quoted," Baxter notes. "But if you don't have big birds around, you have less need for radar detection technology."
Looking at the possibility of further bird-strike legislation, Baxter is cautious: "The key is a better understanding of the drivers. We know a lot, but we can learn more about the use of detection technology in preventing future bird strike risk.
"When a pilot waits to take off and sees birds on the airport, how likely is it that those birds will fly up into the aircraft? A predictive mechanism would be useful in knowing when to stop a flight."
Development is necessary, but the UK is doing well when it comes to the bird-management arena.
"Britain's airports have good systems for habitat management and deterring the remaining birds," Baxter says. "The CAA drives action forward, and the airports are very good at implementing regulations."
However, improvement is needed on the world stage. FERA has worked internationally for many years, and Baxter claims many nations do not have the required expertise or funds. Moreover, the techniques used in the UK and North America are not useful in regions like the Middle East.
"It's about understanding which habitats are not good for wildlife in such areas and recommending them," he says. "We might see something being used for a particular species in a different country that's beneficial here, and vice versa.
"We can take the best practices carried out in the UK and give advice to airports around the world."