OTTAWA—A safety watchdog is recommending changes to the design of taxiways at Pearson International Airport to minimize the risk of a potentially catastrophic collision.That is one of four recommendations made Thursday after a special investigation by the Transportation Safety Board of Canada into a spate of runway incursions — when an aircraft or vehicle inadvertently taxies onto an active runway. In this short video, we placed a camera at approximately eye level for a pilot of a smaller regional jet, which is the most common type of aircraft involved in the incursions. You can see the aircraft leave the runway and taxi onto the rapid exit, you can see some of the lights, signs, and paint markings, and you can see the “hold-short” lines where the crew is supposed to stop.There were 27 incursions between two closely spaced parallel runways at Pearson between June 2012 and November 2017. At busy times, aircraft land on the outer runway and then taxi across the inner runway to reach the terminal buildings. In every case, the pilots had acknowledged air traffic control instructions to hold short of the runway but still entered the protected runway environment.“Despite all the visual cues, including lights, signage and paint markings, professional crews were not stopping in time as required, thereby risking a collision with another aircraft on the other runway,” said Kathy Fox, chair of the safety board.The incidents prompted the safety board to launch a special investigation to examine whether there might be systemic issues such as runway design or air traffic controller procedures that could be contributing to the problem.At Pearson, the incursions most often involved the two parallel runways on the south side of Pearson airport. To help guard against these incursions, painted markings and flashing lights alert pilots to the runway ahead.But the investigation found that elements of the taxiways at Pearson are different than almost every other airport in North America. For example, the hold lines warning of the runway ahead are located immediately following a 65-degree curve and are farther away from the protected runway than is commonly seen elsewhere. All this means the hold lines — where aircraft are expected to stop and await clearance to cross the active runway — are not where pilots are expecting to see them.An aerial view of Pearson Airport Terminal 1. A safety watchdog is recommending changes to the design of taxiways at Pearson to avoid a potentially catastrophic collision. (Rick Madonik / Toronto Star)“These uncommon characteristics present significant challenges for flight crews,” the board said in its fundings.As well, the investigation found that pilots were often pre-occupied with their after-landing checks and weren’t paying attention to the hold line.In its report released Thursday, the board recommends:Air traffic control amend its phraseology so that safe-critical instructions, such as those instructing aircraft to abort a take-off, “are sufficiently compelling to attract the flight crew’s attention, particularly during periods of high workload.”Transport Canada and the the U.S. Federal Aviation Administration work with airlines to amend operating procedures so that post-landing checks are done only after landing aircraft are clear of all active runways.The Greater Toronto Airports Authority change the physical layout of the taxiways to reduce the risk of incursions between the parallel runways. Until those changes can be made, the board is urging the airport authority to make changes to make the runway holding positions more conspicuous.Runway incursions are on the safety board’s watchlist of most pressing transportation concerns, noting that despite precautions, incursions are on the rise at airports across the country. Nav Canada, the company that runs the air traffic control system, had an average of 445 incursions a year between 2013 and 2017. The incidents themselves are often minor, with an aircraft inadvertently entering the protected runway environment, but stopping short of the runway itself. Yet the potential for disaster is significant and more than once, these incidents happened as another aircraft was speeding down the runway on its take-off roll. Over the last two years, 21 incursions were deemed “high-severity” events that could have led to a collision, according to the safety board. Bruce Campion-Smith is an Ottawa-based reporter covering national politics. Follow him on Twitter: @yowflierTOP STORIES, DELIVERED TO YOUR INBOX.