Explanation Needed On The Term "8 Greens"

kimon · Sun Jan 17, 2010 11:55 am

http://www.youtube.com/watch?v=9Zfw3w3FRMA
What is meant by "I got 8 greens from the undercarriage"
Many thanks!

Starlionblue · Sun Jan 17, 2010 12:45 pm

As I understand it "greens" means the gear is down and locked. One green light per leg. However the 747 has 5 legs so that can't be it.

The 747 does have a total of 8 axles on the mains, so maybe something there?

EMBQA · Sun Jan 17, 2010 2:34 pm

Who knows.. just bad acting and made up words. I've read the actual CVR recordings and I don't recall that ever being said...besides, there really is no reason to care about your landing gear being down and locked at that point.

fr8mech · Sun Jan 17, 2010 3:45 pm

There is only one green light on a B747-Classic on the P-3 (or maybe it's the P-2) panel (up front). On the FE's panel, he can 'view' each gear individually using the primary and alternate switches. But, that still only accounts for 5 green lights. The other lights on that panel are amber.

EMBQA · Sun Jan 17, 2010 4:48 pm

I just re-read the KLM CVR and there is nothing like that on the tape. The only thing that comes close is a comment about the leading edge slats.

474218 · Sun Jan 17, 2010 5:52 pm

Quoting EMBQA (Reply 4):
I just re-read the KLM CVR and there is nothing like that on the tape. The only thing that comes close is a comment about the leading edge slats.

On the L-1011 landing check list the FE is to report "14 greens" when asked "leading edge slat". The slat panel on the FE panel has 14 green lights (numbered 1 to 7 for each wing) that illuminate when the slats are full down. There is also a gage that shows slat movement and a slat lock switch.

fr8mech · Sun Jan 17, 2010 7:04 pm

Quoting 474218 (Reply 5):
On the L-1011 landing check list the FE is to report "14 greens" when asked "leading edge slat".

Now, there are 8 green lights on the back panel for the leading edge devices, but I've never heard the call-out in the dozen or so or more times I've ridden up front.

tdscanuck · Sun Jan 17, 2010 7:47 pm

Quoting Fr8Mech (Reply 6):
Now, there are 8 green lights on the back panel for the leading edge devices, but I've never heard the call-out in the dozen or so or more times I've ridden up front.

No standard procedure would have you do that...that panel is considered to be out of the field of view of the flight crew, so you can't use it for normal procedures.

Tom.

747classic · Sun Jan 17, 2010 8:37 pm

Quoting EMBQA (Reply 4):
I just re-read the KLM CVR and there is nothing like that on the tape. The only thing that comes close is a comment about the leading edge slats.

Correct,

KLM 747-200 "Before Take Off" checklist only contained the item :

Flaps ..................................10 or 20, lights green.
(check of the actual Trailing Edge flaps position and the green Leading Edge Flap Light on the Pilots panel, above the vertical tape flap indicator )

Otherwise no green lights were mentioned in this flight fase.

Remark :
The eight amber (transit) and 8 green (fully extended) Leading Edge Flap position lights on the F/E panel are already checked by the flight engineer when monitoring the flap extension during taxi out and are not mentioned. Only the master green L.E. light is checked on the flap indicator at the pilots panel before T/O.

[Edited 2010-01-17 12:47:10]

474218 · Sun Jan 17, 2010 11:18 pm

Quoting Fr8Mech (Reply 6):
Now, there are 8 green lights on the back panel for the leading edge devices, but I've never heard the call-out in the dozen or so or more times I've ridden up front.

I can supply a picture of the "14" green lights on the FE slat panel if you need it.

The following web site describes a tail drag accident that occurred in August 1996. The TWA crew failed to follow the landing check list, which would have identified the failure of the leading edge slats to fully extend, which resulted in a full flap no slat landing. I was part of the NTSB accident investigation team. It was during this investigation that I saw TWA Landing Check List that calls for the FE agreement that all "14" slats are extended by verifying the "14" green lights.

Quoting Tdscanuck (Reply 7):
No standard procedure would have you do that...that panel is considered to be out of the field of view of the flight crew, so you can't use it for normal procedures.

I think you will find that the FE is a member of the flight crew.

http://www.ntsb.gov/recs/letters/1997/A97_97_98.pdf

fr8mech · Sun Jan 17, 2010 11:54 pm

Quoting 474218 (Reply 9):
I can supply a picture of the "14" green lights on the FE slat panel if you need it.

14 green lights for leading edges on the FE's panel? Why and where? There are 8 PDU's, 4 each side. Did they have a green light for each leading edge panel?

474218 · Mon Jan 18, 2010 12:53 am

Quoting Fr8Mech (Reply 10):
There are 8 PDU's, 4 each side. Did they have a green light for each leading edge panel?

If by PDU you mean Power Drive Unit the L-1011 leading edge slat system has only one (1). The slat PDU has two (2) hydraulic motors that turn torque tubes (shafts) that drive the fourteen (14) ballscrew actuators that position the slats.

fr8mech · Mon Jan 18, 2010 1:02 am

Quoting 474218 (Reply 11):
If by PDU you mean Power Drive Unit the L-1011 leading edge slat system has only one (1). The slat PDU has two (2) hydraulic motors that turn torque tubes (shafts) that drive the fourteen (14) ballscrew actuators that position the slats.

I apparently missed the transition from B747 (Classic) to L-1011. apologies, I was talking B747.

tdscanuck · Mon Jan 18, 2010 1:35 am

Quoting 474218 (Reply 9):
Quoting Tdscanuck (Reply 7):
No standard procedure would have you do that...that panel is considered to be out of the field of view of the flight crew, so you can't use it for normal procedures.

I think you will find that the FE is a member of the flight crew.

Indeed. I fell into the same trap that Fr8Mech did:

Quoting Fr8Mech (Reply 12):
I apparently missed the transition from B747 (Classic) to L-1011. apologies, I was talking B747.

Worse, I was talking two-crew Boeing's, not Classics and not L-1011's.

Tom.

747classic · Mon Jan 18, 2010 7:42 am

Quoting Fr8Mech (Reply 12):
I apparently missed the transition from B747 (Classic) to L-1011. apologies, I was talking B747

I never mentioned the L-1011 and stayed with the 747, because I never operated the L1011.

But, let's clear up some things :

I contacted my former (retired) KLM-Instructor what the proper procedure was during that time (1976), because I joined KLM just after the Tenerife crash.

He told me the following :

The phrase "eight greens" was sometimes used by the F/E to clarify that all Leading Edge Flaps were extended.
The correct answer on the item "Flaps" was ................ 10 or 20, lights green

But some answered : 10 or 20, eight greens.

This was not according Standard Operating Procedures but was caused, by the Lufthansa B747-130 crash in Nairobi in November 1974.
This accident was caused by a Take Off made with retracted LE flaps.
Several modifications were made after that accident in the LE logic and warning system to prevent a similar kind of accident.
Some F/E's wanted to check for additional safety all eight LE annunciator lights on the F/E panel before T/O and responded sometimes with "eight greens".
It was a "hot topic" during that time.

But as stated before, "8 greens" was not mentioned on the CVR of the Tenerife accident.

[Edited 2010-01-17 23:58:30]

[Edited 2010-01-18 00:01:03]

kimon · Mon Jan 18, 2010 1:19 pm

747classic!
Excellent!
Many thanks!

474218 · Mon Jan 18, 2010 3:27 pm

Quoting 747classic (Reply 14):
I never mentioned the L-1011 and stayed with the 747, because I never operated the L1011.

It was I who brought up the L-1011. As I explained the term " 14 greens" was the used on the TWA L-1011 landing (and takeoff) check list as the FE response to the the FO's question slats extended. Therefore I assumed other aircraft had the same procedure. Sorry to confuse anyone.

411A · Tue Jan 19, 2010 1:20 am

Quoting 474218 (Reply 16):
As I explained the term " 14 greens" was the used on the TWA L-1011 landing (and takeoff) check list as the FE response to the the FO's question slats extended

Not just TWA, either....every other airline I have flown the L1011 for, used the same verbage/procedure.

Bellerophon · Tue Jan 19, 2010 10:22 pm

747classic

Quoting 747classic (Reply 14):
...I contacted my former (retired) KLM-Instructor what the proper procedure was during that time ... He told me ... Some F/E's wanted to check for additional safety all eight LE annunciator lights on the F/E panel before T/O and responded sometimes with "eight greens"...

Yes, and the same response, for the same reasons, was given by B747 F/Es in BOAC/BA right until the last B747-200 left BA service.

Best Regards

Bellerophon

kimon · Wed Jan 20, 2010 8:12 am

Any photos of LE annunciator lights on the F/E panel?
Many thanks!

dairbus · Wed Jan 20, 2010 5:11 pm

Quoting Kimon (Reply 19):
Any photos of LE annunciator lights on the F/E panel?
Many thanks!

You can see them here on the right above the red door covering the fuel jettison switches.

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