737 Configuration alarm
 

Hi all,

I was a passanger on a Boeing 737 this morning that aborted a take-off due to a "Configuration Alarm"

What are the most likely/common reasons for this alarm?

KDY

The config warning is armed on the ground and when one or both thrust levers are advanced for takeoff. it will sound under the following conditions.
1 the trailing edge flaps are not in the 1 to 25 position for take off or
2 the leading edge devices are not configured for take off or
3 the speed brake lever is not in the down position or
4 the spoilers are not down with the speed brake lever in the down position or
5 the parking brake is set or
6 the stabilizer trim is not set in the take off range.

The above list is not real problem just abort the take off (going to be slow speed reject) and re configure.
Its in the air that that particular horn will indicate a far more bum twitching problem as its indicating a cabin altitude exceedance

hope that answers it for you
Flyfish

Thank you Flyfish, that makes sence with what happened.

KDY

Tell the pilots to do their "3 killers" check when they roll onto T/O position...
Trims-Flaps-Spoilers... Old fart trick...
:D
Happy contrails

It is this one that caught a good friend of mine. The trim was correct but as the aircraft increased speed on takeoff the elevator loaded up and when that happened, the trim was near the forward limit and the config horn sounded. His F/O said, "We aborted for a trim problem..." The FAA violated the crew for failing to conduct a proper pre-flight. Only after lawyers got involved was the crew exonerated.

Yes, I remember....
 

Yes, I remember getting a line check....when I was a line check airman, myself, by some snot-nosed, "ninety-day-wonder" of a check airman. This was back in the old days when I flew the 737-200 (both basic and advanced).

He criticized me for for making such a non-standard callout as we were taking the runway for takeoff: "Killer Items Checked".

In addition, he also had a big problem with my callout for takeoff thrust set. (This was on the P & W JT8D.)....."Thurst Set, all gauges at the nine o'clock position". (This was shortly after Air Florida dumped one in the Potomac River....for those who remember.)

I suspect this guy is still sitting behind some desk touting his flying skills and expertise.....all of his maybe 5000 hours total flight time amassed over 30 years in the business.

I also remember, as a new international captain, making my first over-the-pond flight. I told the senior F/Os....."I know the book. I know the book inside and out. But, based on your experience, tell me how to stay out of trouble."

I took their advice....and I never had a problem......

Fly safe,

PantLoad

When thrust levers moved forward,T/O configuration warning comes on if the following are not adheared to:-

Flaps in T/O range
Stablizers in Green band.
Spoilers retracted.
Parking brake released.

Normally its an indication problem that triggers the warning.mostly observed to be the slat proximity switches.

regds
MEL

@ HAWK21M
please start reading the threads before writing.
Posting #2 have listed the conditions already (and more precisely) :ok:
Yeah.... pushing up the postcounter.... :ugh:

@Ifixplanes....
Post count raising.....you have double the posts in 1/3rd the time since you joined up here in comparism......:bored:Maybe I should be saying the same thing.

Cheers & think positive.Rather than one liners of sarcasim as in your many posts,share your knowledge with the forum.:)

Guess what....I don't need to hide my profile.:=

cheers.

regds
MEL

Mr. Fixer...

Chill dude.... it’s a free forum for one and all.

Hawker was pointing out the fact the more common cause of the T/O

Another common problem is the micro switch associated with the speed brake lever wears out, which is a pain in the butt to change.

Except of 4 postings in 2001 your postings start at 2006. ;)

Well, the edit-function is a nice tool...

Just out of interest, would it also sound if the autobrake was not set to RTO?

No.Not on the 73's I've worked.
Usually (in my experience) speed brake lever not fully stowed.Only takes a poofteenth out of the detent to set off the config warning.
And yes they are a bit of a pain to change.

OK, thankyou.:)

Beep beep beep
 

What I definitely admire here, is the use of modern technologies -
That you replace the "3 killer" check... by a gizmo that, never fails.
Never fails - no CB - no 28 DC - no 115 AC... never fails.
xxx
:eek:
Happy contrails

Providing the stab trim is in the green band the config warning should not sound. Can't quite see how an elevator "loading up" causes a config warning. It is not a C of G warning, but a stabiliser position warning, isn't it?

I have experienced several - mostly due to tail trim on the 'edge' of the band but detected as out by the config system and speedbake mis-setting as described.

BA's wonderful fleet of old 737-200's used also to have LED proximity reed switch problems with monotonous regularity (they were knackered:)) and the config would sound as speed got towards V1 which always made the 200 take-off brief interesting!

hello, just a little addenda:
Classic vs NG TO conf warning:
-TE flaps not in TAKE OFF range which is F1 to F15 for 733 / F5 to F15 for 734&735 / and F1 thru F25 for 737 ng.
- LE DEVs Not extended for TO : Classics take the signal only from LE DEVs 1 and 4 while the NG has a FLAP/SLAT ELECT UNIT (please correct me if I'm wrong)
- I am not really sure of the point 4 of flyfish "4 the spoilers are not down with the speed brake lever in the down position or"...never herd that and no trace on books but maybe for the classics is a different story
- TAKE OFF conf warning sounds when either or both THRUST LEVERS pass 30° for classics and 53° for NGs

During the take off roll, building up speed, the aerodinamical loads on the elev and stab could create a dual failure of the brake sys thus giving you a STABILIZER RUNAWAY and a TO CONF WARNING. Really dunno if aerodinamical loads on elevator moving upwards could effect a little stab position!I'd be glad to have info! Grazie

ciao.

It might be an option, but newer NGs have two additional lights that tell you if its a config or cabin altitute warning.

If that’s the case Denti, I have learnt something there, so glad I am involved in this thread.
Cant see why you would want the lights though, if its on the ground it’s a config, if its in the air, my Oxygen mask is going on. The config light would never illuminate (well never say never) airborne, you don’t need the lights as the two problems are worlds apart in terms of operations. That said I guess with the onset of hypoxia a second more clear warning light with the words ‘cabin alt’ may save the day, but cabin alt on the ground? Contradicted myself there a little as I explored the reasoning while typing, so sorry if this is waffle.