ERJ135

NTSB ADVISORY
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National Transportation Safety Board
Washington, DC 20594
June 29, 2007

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NTSB INVESTIGATING LANDING GEAR MALFUNCTION

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Washington, D.C. - The National Transportation Safety Board
is investigating an incident in Boston that occurred on June
20, 2007, in which an American Eagle Embraer ERJ-135
regional jet briefly touched down on the runway without the
landing gear extended before initiating a go-around and
completing a second landing attempt.

None of the 37 passengers or 3 crewmembers was
injured. The aircraft sustained minor damage. The event is
being investigated as an incident.

Prior to the first landing attempt in which the gear
was not extended, the crew stated that the three landing
gear indicator lights were all green, indicating that the
gear was down and locked. Shortly before touchdown they
noticed a "landing gear lever disagree" message on a flight
computer console.

After the jet contacted the runway, a go-around
procedure was initiated. The crew extended the gear by
following the emergency abnormal landing gear procedure,
then flew by the control tower twice for a visual inspection
to ensure the gear was down prior to the second landing
attempt.

At this point in the investigation the following has
been accomplished:

In an initial test, the incident aircraft was placed
on jacks and investigators duplicated the in-flight
situation: Three green lights in the cockpit indicated the
gear was down and locked but none of the gear extended.

The cockpit voice recorder and flight data recorder
were sent to the Safety Board's laboratory in Washington
last week where the content of each is being evaluated.

Both members of the flight crew were interviewed this
week.

An electronic component of the landing gear control
system, made by Parker Aerospace, was bench tested this week
at their facility in New York. The same unit, with small
modifications, was then placed in a different airplane and
the indications were once again duplicated.

Embraer issued a "Field Service Letter" late last week
to all operators of the EMB-135, -140, and -145 models,
reminding pilots to follow the checklist in the case of a
"landing gear disagree" message.

The Federal Aviation Administration, Parker Aerospace,
American Eagle and Embraer are working with the Safety Board
as the investigation continues.

##

NTSB Press Contact: Peter Knudson
202-314-6100
[email protected]

Link to Parker LGEU:
http://www.parker.com/EAD/displayCat...&sMode=Details

UnlimitedAkro

I wish someone would send that to Fox News in Boston.

That newscaster made her live news report (the day of the incident) sound like the whole thing was all pilot error and the crews forgot to put down the landing gear...

It's pretty scary to think that these pilots got 3 green lights with the whole gear system fully up.

cbire880

Yeah, but dending on when that lever disagree message showed up, someone may still go after the pilots for not seeing it and executing the checklist. That was Embraer's solution. The rest of the world will find some way to string up the pilots, don't worry.

rickair7777

I don't understand how you could possibly design a system that way...especially on a transport category aircraft.

Three green lights should be activated from three SEPERATE circuits, each of which should derive it's condition from redundant position sensors.

Ellen

Brazillians!

UnlimitedAkro

i hear that.... but it may not have been their fault.

Embs are run completely by computers. Everything. The engines are run by computers... the APU... pressurization... climate control... flight instruments... All computers.

And the company that makes the computers for the landing gear system is not Brazilian...

G-Dog

This is absolutely crazy. I guess we will need to do a fly-by near the tower before landing from now on. Add that to the checklist.

2Lazy

Is it really that quiet in the EMB? You would think they would be able to hear the gear either come down or not?

avi8tor4life

Chinese maybe?

SharkyBN584

No, it's not that quiet. Problem is...most of the noise is generated by the gear doors right below the pilots feet when they open. The AE plane had the gear doors open, just no landing gear. So, other than the satisfying "thump" you get when the gear slams into place, it would have sounded pretty normal to them up front...