Wing Clipping Incident Underscores Need For Cockpit Collision Alert

Based on the collision of an Air France A380 super-jumbo with a Comair regional jet on the evening of 11 April 2011 at New York’s JFK International Airport, this “Most Wanted” recommendation issued in 2000 by the National Transportation Safety Board (NTSB) will doubtless receive added impetus: “Give immediate warnings of probable collisions/incursions directly to flight crews in the cockpit.”

The recommendation to the Federal Aviation Administration (FAA) has been color-coded by the NTSB as red for “Open – Unacceptable Response.”

There are eight pages of fine print notes summarizing letters back-and-forth between the FAA and the NTSB since the recommendation was first issued. The last letter from the FAA, in 2009, indicated that a pilot project “will support development of requirements and an acquisition strategy …” etc. etc. The FAA response was neither timely nor promising.

It may be useful to compare the aviation industry to the automobile industry. During the past decade, automobile manufacturers have developed collision-avoidance cruise control and hands-free parallel parking. Both applications involve the detection of obstacles (e.g. cars and curbs).

The FAA, in concert with industry, is developing the Next Generation (NextGen) air traffic control system. Built around ADS-B (Automatic Dependent Surveillance – Broadcast), airplanes will broadcast their positions to air traffic control. This is known as ADS-B Out. A complementary application, called ADS-B In, would broadcast information into the cockpit. Under ADS-B In, the two aircraft involved in the collision at JFK would have been broadcasting their location to one another, providing the essence of a collision avoidance system. Under the initial concept of NextGen, ADS-B Out will be featured but not ADS-B In.

As the essence of collision avoidance the NTSB seeks, ADS-B In remains a distant dream. Application of automobile collision avoidance to taxiing aircraft as a “good enough” solution has not been even considered.

The NTSB justifiably concluded in 2009:

“This recommendation is now 9 years old, and it has been on the Most Wanted list almost since the recommendation was issued … technologies have not yet been finalized nor scheduled for deployment ….”

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There has been no update since. Now the NTSB is investigating the incident at JFK and will doubtless take the opportunity to reiterate its stalled safety recommendation.

Back at the gate after colliding with the regional jet

Back at the gate after colliding with the regional jet. Photo Attribution: © Antoine FLEURY-GOBERT / Wikimedia Commons / CC-BY-SA-3.0

The Air France A380 was taxiing from the boarding gate to the runway for a flight to Paris. A Comair CRJ700 operating as Delta Connection was pulling into its gate, but had halted, waiting for ramp personnel to marshal the small commuter jet the final few yards into the gate. The CRJ700 had arrived from Boston.

The huge Air France A380, its 262-foot wingspan overhanging the 75-foot taxiway, struck the much smaller CRJ700. The impact spun the CRJ a full 90 degrees, just missing a person on the ramp who was walking out to escort the small jet to the gate. In a video of the collision, the ramp person can be seen jumping back as the CRJ700 rotated violently approximately 90 degrees. The 62 passengers aboard received quite a scare.

Grainy photograph showing the CRJ700 being spun 90 degrees

Grainy photograph showing the CRJ700 being spun 90 degrees

A pilot aboard the CRJ700 radioed the tower: “Roll emergency trucks. We’ve been hit by – uh – Air France.”

The larger jet halted after being seemingly unaffected by the collision. However, the left wingtip of the A380 was damaged and the jet returned to the terminal to offload its 520 passengers and await repairs. The CRJ700 had been struck on the vertical fin, which also required repair.

Damage to the A380

Damage to the A380

Damage to the CRJ700

Damage to the CRJ700

The A380 is equipped with a closed-circuit television system (CCTV), which apparently was of little use in alerting the pilots to the presence of the CRJ700. The CCTV features a panoramic camera mounted high in the tail and four additional cameras mounted below the fuselage to track the landing gear. The system is intended to help prevent the landing gear from rolling off the taxiway when the A380 is making wide, off-center turns. Since the A380 was engaged in straight line taxiing at the time of the incident, the pilots may not have been looking at the video feeds.

With a restricted field of view from the A380 cockpit, preventing the pilot from viewing the wing clearly past the outer engines, the pilot taxiing the A380 clearly did not see the much smaller and closer-to-the-ground CRJ700.

One pilot remarked:

“With the large aircraft, it really does not matter if you are on the center line of those taxiways – their width at JFK is 75 feet. The A380 has a 260-foot wingspan. To me that means the pilots have to be extra careful to ensure wingtip clearance.”

The role played by the tower controllers will most definitely be examined by NTSB investigators. Additionally, if the A380 was on the center line of the taxiway, what was the responsibility of the Comair pilots on the ramp to ensure proper clearance?

In automobile terms, who had the right-of-way?

JFK and other airports serving the A380 have had taxiway turns modified to allow the landing gear to negotiate the wider radius without departing the paved surface. Terminal gate areas must meet a box 262 feet on each side, or template, to ensure adequate clearance from structures.

Had the NTSB’s 2000 recommendation been adopted by the FAA, the A380 cockpit would have featured a warning of the threat that likely would have enabled the pilots to take action and prevent the collision.