Air Canada Too Low Into La Guardia ?

[Kip Powick]

OTTAWA—An air traffic controller had to alert the pilots of an Air Canada flight after they descended too low during a bad weather approach to New York’s La Guardia airport.

The airline has launched an internal probe into the Nov. 27 incident involving Air Canada Flight 748, which happened as the twin-engine Embraer 170 jet was arriving from Montreal.

The pilots were using elec

tronic aids to guide the aircraft through the low clouds, rain and late-day darkness to a landing on Runway 4 and had been told by air traffic control not to descend below 520 metres until passing an approach fix.

But with autopilot engaged for the approach, the Embraer jet started down to the runway too soon, busting the altitude restriction issued by the controller, according to a preliminary report prepared by Transport

Canada.

The jet — still enveloped in cloud — continued down and was just 300 metres above the borough of Queens when the controller sounded the alarm about the premature descent.

“The aircraft was one mile outside the (fix) when it reached 1,000 ft. and (air traffic control) issued an Altitude Alert,” the report said.

The pilots quickly aborted their faulty approach, circled around and made a successful landing at the busy airport on their second try.

The Transportation Safety Board of Canada conducted a preliminary investigation into the incident but has handed the file over to the airline to pursue internally, a spokesperson said Thursday.

Airline spokeswoman Isabelle Arthur said the controller told the crew that there “appeared to be a discrepancy with the aircraft altitude indication.”

“As per operating procedures the crew did a go around and landed without incident,” Arthur told the Star in an email. “These types of events are extremely isolated and we always conduct internal reviews to ensure we maintain the highest levels of safety standards and operations.”

Arthur did not say whether the discrepancy had been attributed to human error or a mechanical problem.

[Seeker]

False G/S capture? (which I'm not saying is an excuse for failing to catch the early descent).

[airt]

False G/S capture? (which I'm not saying is an excuse for failing to catch the early descent).

Looks like they were on an RNAV approach

http://www.avherald.com/h?article=45a21558&opt=0

[neverminds]

Maybe left the altimeter at 29.92?

[Seeker]

Maybe left the altimeter at 29.92?

Possible but not likely - the Embraer annunciates this error.

[DEFCON]

Too much typing and not enough piloting?

[Dork]

You certainly get what you pay for.

Quality spin...

Dork

[Seeker]

You certainly get what you pay for.

Please clarify. I'm not sure who you're trying to insult.

[Fido]

Please clarify. I'm not sure who you're trying to insult.

He doesn't care who, he just wants to insult.

[Dork]

Seeker...unless you were asleep during the FOS..nothing more needs to be said.

Take the time to check it out.

Don t worry though... It funds Fido s pension and he is happy. Just another flea on the back of the JR pilot.

Dork

[inchman]

I don't know what his post says because I've had Dork on IGNORE for a couple of years. Until that point, at least, he's never said anything worthwhile reading and it would appear that that situation hasn't changed.

[Kip Powick]

OTTAWA—For the second time in just over a week, an air traffic controller had to warn the crew of an Air Canada jet after they flew too low during their approach to New York’s La Guardia Airport.

Now airline officials are wondering if there is a gremlin in the electronic navigation brains of the Embraer jet that is somehow leading the aircraft astray.

The most recent incident happened on Dec. 9 as Air Canada Flight 730, an Embraer 175, set up for landing after a flight from Toronto.

According to a report on the website The Aviation Herald, the aircraft descended below the minimum altitude during the approach to Runway 4, prompting a La Guardia controller to warn the pilots. The aircraft climbed up to a safe altitude and continued the approach.

The incident is an almost exact replica of a Nov. 27 flight that also descended too low during its approach to the same runway, prompting a warning from the controller about their deviation.

In that case, the pilots of the Embraer 170 immediately aborted their approach and were steered back around to make an uneventful landing on their second attempt.

In both cases the autopilot was in operation, guiding the flight along what should have been a precise path to the runway.

After the first incident, airline officials declined to say whether they were looking at a mechanical problem or human error.

But now, with second strikingly similar incident, it appears more likely that the problem could lie in the airline’s procedures or the jet’s navigation software. Like GPS units for cars, the database for the navigation software must be updated periodically. It is possible that the most recent update contains an error in its data for this particular approach.

Air Canada spokesperson Isabelle Arthur confirmed the airline is investigating two similar incidents.

“During both approaches the crew followed all Standard Operating Procedures and all path corrections were completed well above the alerting thresholds,” she said in an email. “At no time were the passengers and crew in any danger.”

Both flights were flying what is known as an area navigation approach (RNAV) that uses satellite signals as well as ground-based navigational aids to help steer the aircraft to the runway.

The airline has told its pilots to no longer use this approach at La Guardia until the problem is sorted out.

A spokesperson for the plane’s manufacturer confirmed it is looking into the two incidents.

“Embraer has been informed by Air Canada of these events and we are currently gathering information to better evaluate the matter,” Elisa Donel said in an email.

A spokesperson for Honeywell, which makes the aircraft’s electronics, including its navigation systems, confirmed it too is working with Air Canada and Embraer on the problem.

Embraer jets are widely used in the United States, and Honeywell and Embraer said they’ve had no other reports of this problem from other airlines.

[Thebean]

Gremlins.

Just another gift Roald Dahl gave to the world.

[deicer]

Just one question.

If the softwear was faulty, don't they have the charts out as backup? Is it not crosschecked or is it total reliance on tech?

One would think if one was wrong, the other would be right?

Sorry, I know that was three questions.....

[Don Hudson]

ed. Deicer, good question(s).

It should be pretty straightforward to determine if the database was in error, ie., if the FAF crossing altitude was lower than the published altitude, which seems to have occurred here. But if the database was in error it could only be a contributing factor. I think the problem and lesson here is permitting the airplane to descend below a published approach altitude. Distance-and-altitude checks especially at the FAF are SOPs so it will be more interesting to understand how an early descent below the FAF altitude occurred.

[Boney]

One usually check the FMC waypoints and altitudes using the plates. If there was a discrepancy, then one is obliged to not use the FMC.

If correct, then one way of going below a hard altitude is to set field elevation in the MCP, then select altitude intervention to change the next hard altitude.

I'm only guessing, so it is prudent to await the investigator's report.

Merry Christmas chaps, and blue side up.