Caribbean B738 at Georgetown on Jul 30, 2011, overran runway [Archive]

Escape Velocity

30th Jul 2011, 12:35

Sorry to see this - I flew into GEO for about two years in the 757. 7500' for Rw 06, the ILS never worked the entire time I flew in there, and was never notamed as out. The VOR approach can be interesting since the DME didn't work either. I had more map shifts there than I've ever seen before or since. Add to that the closest realistic alternate is POS, so you tanker a bunch of fuel in addition to (usually) max payload. Add the occasion tropical downpour and it can get interesting!

Good catch on flap position - I bet that was a big jump from the overwing exits. Can't imagine an -800 even trying it with less than full flaps. One wonders how they managed to be "up" when the reversers are still deployed?

I always thought my career had hit rock-bottom when I did an overnight there. Haven't seen too much worse, but Khartoum comes to mind!

Walder

30th Jul 2011, 13:02

Why land without flaps???
They must have some kind of problem prior landing then!
Otherwise?

ross_M

30th Jul 2011, 13:36

Pretty impressed that no deaths for a crash like this one.

Among the injured was Geeta Ramsingh, 41, of Philadelphia, who said passengers had just started to applaud the touchdown "when it turned to screams," she said, pointing to bruises on her knees.

Do people applaud landings frequently? Or was there some sort of sense of impending disaster that the touchdown alleviated?

NG_Kaptain

30th Jul 2011, 14:11

Cannot explain why the pic shows the flaps/slats retracted. I have thirty plus years experience into GEO with the predecessor airline to Caribbean and we always landed with max flaps for the type due to the challenging approach, normally bad weather and short and slippery runway. If I remember the 737 if you did not get full weight on wheels you can only get partial spoilers and idle reverse. Maybe when the over run was inevitable they retracted them.

chock2chock

30th Jul 2011, 14:16

Isn't the clean speed af a 737 with 150 pax something in the region of 190-200kts? Unlikely that they would have conducted an approach and landing at that speed thats like 50kts more than with full flaps! Not to mention all the red lines that would appear on PFD speed tape...

Jonnie Chan

30th Jul 2011, 14:17

Possible explanation may be that during the evacuation checklist, which calls for F40 selection, if not already selected, the flaps were inadvertently retracted. Seems unlikely that the crew would have attempted a landing without flaps/slats set. Imagine the landing distance requirement.
Praise the Lord for no loss of life.

Carbon Bootprint

30th Jul 2011, 14:25

Do people applaud landings frequently? Or was there some sort of sense of impending disaster that the touchdown alleviated? In some cultures, notably the Caribbean/South America and parts of Asia, this is not uncommon. Those are the places where I've seen it happen, though I won't say it necessarily happens on every landing in those places.

ZQA297/30

30th Jul 2011, 17:27

Timehri (now Cheddi Jagan) is well known for night fog. As someone else said, the ILS is there in name only most of the time. Those who know it treat it with great respect.
BWIA had 2 over-run incidents in the distant past, none of them as serious as this.
A Viscount overrun that was due to reverted rubber hydroplaning, and an MD-83 that was hit by lightning on the T/O roll and aborted (below V1) and overran. The runway was noted for slipperiness
Too early to speculate what happened, or why it happened, but when BWIA was closed, many of the more experienced pilots were picked up by sandpit operators. The pilots union was squeezed out, and a new philosophy was put in place. Let us say it was slanted to "productivity".
They say that a safety culture dies slowly unless nurtured carefully.
It has been 5 years since the old regime was broken up, I hope the replacement will stand scrutiny in the investigation.

DC-ATE

30th Jul 2011, 18:22

As to the lack of flaps/slats.....perhaps that particular Captain retracted them at touchdown on short runways to dump the lift and, supposedly help with the stopping. Just a thought. I never did that but it WILL work.

ZQA297/30

30th Jul 2011, 19:30

Soft touchdown on wet runway.......not good.
Policy in Georgetown used to be "no greasers", put it down firmly and get spoilers and reverse fully engaged asap. Braking unpredictable. Not so, NG?
I doubt that has changed.

Machaca

30th Jul 2011, 20:15

http://i337.photobucket.com/albums/n385/motidog/BW001.jpg

http://i337.photobucket.com/albums/n385/motidog/BW002.jpg

http://i337.photobucket.com/albums/n385/motidog/BW003.jpg

Walder

30th Jul 2011, 20:30

Sorry, but I don´t believe the flaps were out. If you land with full flaps, it takes actually quirt some time to retract the flaps. And I do not believe it was done deliberately after the crash – I don´t think there is any connection to the flaps nor any functional hydraulic system – they must have broke. I just wonder!

waves-dubai

30th Jul 2011, 20:52

chock2chock

30th Jul 2011, 21:18

The speed between 0 flaps and vref 40 is like 60kts.

Walder

30th Jul 2011, 21:19

The evacuation checklist on the 737NG:

Parking brake …SET
Speedbrake lever … DOWN
FLAP lever ….40
Pressurization mode selector… MAN
Outflow valve switch… OPEN
Hold until the outflow valve is fully open.
If time allows, verify that the flaps are 40 before the engine start levers are moved to CUTOFF.
Engine start levers (both) … CUTOFF
To be continued….

The reason for the flaps is set to 40 is to assist the evacuation from the overwing exit. The passengers can slide on the flaps.

Walder:p

Broomstick Flier

30th Jul 2011, 22:21

By the damage inflicted to it, would it be safe to assume a runway excursion on a rather low forward speed? Lets say, below 100kt?

The wx conditions at around the misshap time:
SYCJ 300600Z 00000KT 9000 BKN015 24/24 Q1008 NOSIG
SYCJ 300500Z 00000KT 9000 -SHRA FEW014CB BKN015 25/24 Q1009 CB-NE-ENE NOSIG
SYCJ 300423Z 00000KT 9999 TS FEW015CB SCT016 CB-NE-ENE NOSIG

Seems they were trying to stop it until the last moment

PH-MVK

30th Jul 2011, 22:40

FirstStep

30th Jul 2011, 23:28

Operated in/out of Georgetown for 6+ years in the B-707. As previously mentioned, the ILS was "intermittant", often going OTS in bad weather. Had the runway lights stolen ( copper $$ ) twice. So, security no so secure.
Short runway, often wet, ILS untrustworthy, lighting probably works, in a very black hole in the jungle. Fun times.
I have to say though, I worked with some of the nicest, giving people I ever knew ( Guyanese ).

dwshimoda

30th Jul 2011, 23:28

Seeing the AA pictures just serves to remind that the airline industry is not learning (and relearning) fast enougth.

Yes - you're spot on - it's definitely an identical set of circumstances and clearly no lessons have been learnt... :ugh: Pillock.

Broomstick Flier

30th Jul 2011, 23:58

Many here are mentioning the ILS, funny enough I am unable to find any chart for the said ILS (neither for 06 or 24) on my jeppview software, properly updated. Gone for good?

There are four IALs available: two RNAV (24 and 06) and two VOR (06 only)

Winton

31st Jul 2011, 00:44

'Maybe it says something about the quality of the pilots / planes in those regions'

Not sure what Ross M meant, but i wondered how long before this kind of insinuation would come out.. funny didn't hear this when AF overran in Montreal, Iberia in Colombia or somewhere down there with the 340, when EK did a great deal of damage in JNB or AA in Kingston recently, etc., etc.

Come on guys.... it may well be human error, but lets not regionalize it.

I do agree from first-hand experience that there seems to be an inordinate amount of credit given for smooth landings as an indicator of good performance in the region, and i agree with other commentators that this certainly would not have been an occasion for such a landing if the weather reports and assumed runway surface condition is correct...

flox

31st Jul 2011, 01:06

B738 landing distance with all flaps up

Includes 305m air distance from threshold, max reverse and max manual brakes

Dry RWY 1225m / 4020ft

Medium braking action 2340m / 7670ft

Poor braking action 3090m / 10200ft

Problem with flaps, distant/bad weather alternate, checked the books and decided that they can just make it. Got caught between assumed and actual
braking action or by some of the adjustments for speed/weight/slope of the
basic distance, another 100-200m.

Pontius

31st Jul 2011, 01:13

A FA friend mentioned, on B738s, once the emergency evacuation is activated,the flaps will retract to allow pax to use the overwing exits as an evacuation area...

How is the that going to happen? You've shut down the engines and pulled the engine fire switches, therefore there's no hydraulic, nor electrical power. The flaps can't just magic themselves up. Maybe some further reading required of your FA friend.

NG_Kaptain

31st Jul 2011, 06:42

As ZQA commented

Too early to speculate what happened, or why it happened, but when BWIA was closed, many of the more experienced pilots were picked up by sandpit operators. The pilots union was squeezed out, and a new philosophy was put in place. Let us say it was slanted to "productivity".
They say that a safety culture dies slowly unless nurtured carefully.
It has been 5 years since the old regime was broken up, I hope the replacement will stand scrutiny in the investigation.

I do hope they can stand an audit. Most of the trainers and fleet managers from the old BWIA along with more than half the line pilots plus the same with the ex Air Jamaica pilots who were merged had to find new homes, mainly in the UAE, UK, US and India.

ReverseFlight

31st Jul 2011, 08:26

From my NG Cockpit Companion, the horn is activated if flaps up through 10 and thrust levers are set for landing. From my memory the horn is loud enough to wake the dead.

cochise

31st Jul 2011, 09:28

It's a sad day for Aviation in Trinidad. No hull loses from a national carrier in history. A sader day for the crew...
This could happen to anyone so think about that before you hang anyone out to dry.

ZQA297/30

31st Jul 2011, 09:30

@Reverse flight.
Plus GPWS yelling "too low, flaps!!"
I doubt the approach was made without flaps, unless pilots were totally deaf.
If memory serves me, policy on flap/slat retraction was "clear of runway, with aircraft under control". I dont think both conditions were met.

Walder

31st Jul 2011, 09:40

But they could have had a problem - we do not know!!

contractor25

31st Jul 2011, 11:36

I doubt anything aft of the fuselage fracture would be still controlable from the flightdeck.
It is possible to retract/extent flaps/slats with the electric pumps but when the electrical wires are severed between flightdeck and pump it will not be possible.
This of course goes for all other systems which are controlled in similar fashion.

akerosid

31st Jul 2011, 11:55

Just following up on some comments made about the airline's training, I note that in the days leading up to this incident, the carrier added two more 738s (one brand new, 9Y-SXM, from Boeing, and another, 9Y-JMF, which was delivered from SNN on the 28th), with a third, 9Y-JMC, to be added imminently; I know it's not a large airline and presumably this addition of new aircraft would have put a lot of pressure on the airline's training dept.

Do we know anything about the experience of the crew involved in this incident?

ross_M

31st Jul 2011, 12:05

I doubt the approach was made without flaps, unless pilots were totally deaf.

Mere speculation, but could there be any conceivable malfunctions causing inadvertent flap retraction just about touchdown? That'd explain a lot of the inconsistencies.

Avenger

31st Jul 2011, 12:16

A FA friend mentioned, on B738s, once the emergency evacuation is activated,the flaps will retract to allow pax to use the overwing exits as an evacuation area...
There is no way, this plane would have landed with 0 flap settings...

? What is the " emergency evacuation" this does not exist... evacuation checklist are read and do items on back of QRH, not some magic button that starts the process.

If time allows verify flaps are at 40 etc etc..

If the hydraulics fail the flaps/slats lock out not retract.. that's why we have hydraulic fuses

Mimpe

31st Jul 2011, 12:44

Flox- you have the estimation for their required landing distance flaps up with poor braking action at well over 3000 metres. A quick look at the reported runway length of 7540 ft makes it something that was never going to happen.

wingview

31st Jul 2011, 14:40

I thinks they already selected flaps up during the landing roll and when finally stopped obviously not able to select flap 40 again. To me more interesting, did they use reverse untill 60 kt, were they braking from the beginning till the end, and what was the AB setting? That's probably something we'll read in the report...

Walder

31st Jul 2011, 15:21

The reversers seems open = have been used intil the crash.
But when they been opend is so far unknown.

Oilhead

31st Jul 2011, 16:21

Why would someone select flaps up during the landing roll?

Melax

31st Jul 2011, 16:28

Go around perhaps ?:ooh:

JW411

31st Jul 2011, 16:36

"Why would anyone select flaps up during the landing run".

A F/O did this to me without being asked just seconds after touch down on a very wet runway one night. He told me that it made the aeroplane sit down better. He had come from DC-3s!

After my debrief, I doubt he ever did such a daft thing again (unless he went back to DC-3s).

Avenger

31st Jul 2011, 17:47

Go around perhaps ?

Go Around after reverse selected.. no.. but go-around would not be at Flap 0 in any event,,

As for "unweighting" the aircraft.. ground spoilers do that job... retracting flaps would have no positive effect and is certainly a wreckless action during the high speed regime of roll out.

Lets see what the CVR reveals :ok:

Walder

31st Jul 2011, 17:51

A flapless go-around is the same as a takeoff without flaps.
Normally you will not survive that.
The normal go-around flaps setting is 15. (Or 1 if the approach was conducted with flaps 15 - single engine.)
And if it was a go around, why is the reversers open then?

I doubt flaps were selected up deliberately – the travel time takes easily 25 seconds from 40 to 0.

Again – no flap motion can have taken place after the crash, the flaps motors needs inputs from the cockpit, and is driven by the hydraulic system, whist must be broken when we look at the pictures. The alternate system (an electrical motor) can only deploy the leading edge flaps and slats, not retract them.

A flapless landing is very rear on the 738 – if ever have happened - but if so, you will follow the checklist, and have declared EMERGENCY, because you land with much higher speed, and that might end up in an uncomfortable situation. So IF an EMERGENCY were announced the rescue team should have been at the plane before the passengers had time to take a taxi…..(according to the newspapers….)

If the configuration horn did not sound – (that happened in the Madrid accident) they should have been suspicious to the indication on the speed tape, and IF they had tried to fly with the speed for flaps 30 or 40 (but with flaps up) they would have stick shaker too. Furthermore the Ground Proximity Warning would have shouted “Too low – FLAPS” – as another on this forum already have mentioned. (As I remember it is not in connection with the configuration warning – so it should have sounded as well!)

I still really wander what happened here?????

Machaca

31st Jul 2011, 18:06

Plenty of chance for damage to wiring to actuate flap retraction...

Walder

31st Jul 2011, 18:21

Only electrical - and then the leading edges will not retract - they can´t!
The hydraulic flapsmotors can not operate if the lines are broken, and the lines goes to the nosegear too - they must be broken!

But let´s se what the investigators finds - maybe I AM vrong:ouch:

simtronix

31st Jul 2011, 19:41

This is from a local newspaper in Trinidad. I have not posted the whole article, only the relevant portions. While his name is mentioned in the link, I have removed his name from the excerpts below.

Trinidad and Tobago's Newsday : newsday.co.tt : (http://www.newsday.co.tt/news/0,144765.html)

'I DID MY BEST TO SAVE LIVES'

By Nalinee Seelal Sunday, July 31 2011

Trinidadian pilot , who crash-landed an Air Caribbean Boeing 737-800 at the Cheddi Jagan International Airport early yesterday morning, told relatives in Trinidad that poor visibility due to heavy rainfall resulted in the aircraft over-shooting the runway, but insisted he did his best to prevent the loss of lives.

The pilot 52, who was traumatised by the incident and suffered injuries to his legs, spent some of the time nursing his injuries at the Pegasus hotel in Guyana yesterday, but when Sunday Newsday telephoned to speak with him last evening he had already checked out of the hotel.

However, a relative of the pilot, who preferred not to give her name, said his main concern was ensuring that no lives were lost when he negotiated the aircraft on the runway early yesterday.

He reportedly said the runway had poor lighting and this contributed to the poor visibility when he attempted to land at about 1.32 am. the captain, his co-pilot and crew members are expected to receive counselling from professional counsellors in the coming days, the Sunday Newsday was told.

Sunday Newsday understands that the pilot’s wife was distraught on learning of the incident and gave a prayer of thanks that her husband and others aboard the aircraft escaped serious injuries. It remained unclear yesterday when he will be returning home.

.........................

According to reports, the pilot barely missed going into a 200-feet wide ravine; this could have resulted in dozens of deaths. Following the incident, the airport was closed, leaving hundreds of passengers from other parts of the region stranded. The airport was reopened at 11 am yesterday.

..............

According to reports reaching Sunday Newsday, the aircraft, which is valued at US$38 million, left New York and made a stop in Trinidad before eventually landing in Guyana. The airline said it was carrying 157 passengers and six crew members.

...................

Hours later in Guyana, Nicholas hosted a news conference, where he stated that it was too early for any preliminary comment about what may have caused the crash-landing. He added, however, that the United States Transportation and Safety Board, as well as the Guyana Civil Aviation Authority, will be conducting investigations into what happened.

swm

1st Aug 2011, 00:47

May/may not be related but definitely worthy of scrutiny... Dateline, a current affairs program in Australia, did a story just last month about three other 737NG aircraft that have crashed on landing and broken up because of defective parts by a Boeing supplier which Boeing ignored even after two employees made them aware of the problems: "They say they couldn't keep quiet any longer over defective parts being made by a subcontractor, Ducommun (http://www.ducommun.com/das/Default.aspx), which they say were then allowed into 737 Next Generation planes between 1996 and 2004… some even had to be hammered into shape or packed with filler to make them fit."

See the story and read the transcript here: SBS Dateline | A Wing and a Prayer (http://www.sbs.com.au/dateline/story/about/id/601201/n/A-Wing-and-a-Prayer)

chock2chock

1st Aug 2011, 01:08

The prospect of a flaps up landing would probably incur a return to TTPP where the runway is long enough and there is a mx. base and also not raining. SYCJ with its sub-par short runway away from a maintenance base is quite blatantly not ideal.

glhcarl

1st Aug 2011, 02:01

The way the fuselage bent could (and I stress the word could) have moved the slat/flap cable run to the retract position. Assuming the engines were still running or at least wind milling there would have been enough hydraulic power to allow the slat/flaps to retract.

I would think a no slat/flap landing would have resulted in a much longer over run.

CHABRIAS

1st Aug 2011, 02:14

The same story claimed the Turkish Airlines 737 at Amsterdam broke up after overshooting the runway. It never made it to the runway! A plane dropping the way it did from the height it did - effectively straight down - is going to break. All the people interviewed were ex-employees who may or may not have had an axe to grind. I'm sure the relevant authorities would notice a fault given the number of examples but so far no alarm has been raised by the NTSB etc. Simple fact is - planes travelling at high speed off the end of runways tend to get damaged.

caber

1st Aug 2011, 11:51

Once my airplane departs a prepared surface at high speed I stop really caring whether or not the airplane survives to fly again. Once that excursion is made, the only thing that really matters are the people on the plane. In this case, the airplane did as well as anyone can ask considering the lack of fatalities.

Magplug

1st Aug 2011, 14:57

From the pictures....

Translating sleeves are still aft. Forward idle has therefore not been selected.

No flaps, slats or spoilers.... So no hydraulics you say ? So how did they apparently select reverse on both engines without hydraulics ?

On landing you normally select reverse idle by 60 kts and forward idle at taxy speed. Looks like these guys never reached taxy speed on the rollout. After landing cx with selection of flaps/slats up would follow selection of forward idle..... not precede it.

An inadvertent selection of flaps up on landing roll maybe ? That would stow the spoilers and make stopping far more difficult. But what would you be possibly doing during the landing roll to mistakenly select the flaps up? When landing on a short wet runway all eyes are on the decel and the remaining distance... not pulling levers.

http://img.ibtimes.com/www/data/images/full/2011/07/31/140744-caribbean-airlines-crash.jpg

http://msnbcmedia2.msn.com/j/MSNBC/Components/Photo/_new/110730-plane-hlg-2p.grid-8x2.jpg

This was a very slow speed upwind excursion where 10-15 feet of level wet grass would have stopped the jet. Unfortunately that was not the lie of the land.

Maybe the speed was under control on landing, the after landing checks were in progress and as they approached the runway end.... someone inadvertently selected TOGA? Stranger things have happened! Or simply a case of speed misjudged ?

Cough

1st Aug 2011, 15:28

Just a theoretical possibility, from someone with no NG experience..

During the excursion, the fuselage broke. The flap lever may have mechanical linkage to the control system in the wheel well. The linkage may have been pulled to the retracted position during the fuselage fracture. I'm sure the hyd lines that service the NLG extension/retraction/NWS would have been severed, but thats served by system A. System B therefore remaining intact to retract the flaps by either an idling engine or windmilling core rotor of the no2 engine.

Shoot me, its just a theory!

ZQA297/30

1st Aug 2011, 15:53

I think I am seeing some spoiler panels up, but a strange mix. Dont think it is possible to get that config in a normal manner, so hydraulics/selectors are somehow out of kilter. Possibly same problem with flaps? Post impact damage?

ross_M

1st Aug 2011, 17:02

This was a very slow speed upwind excursion where 10-15 feet of level wet grass would have stopped the jet. Unfortunately that was not the lie of the land.

Wish more runways had crushed concrete arresting pads at the end. Can't be that expensive? I remember Chicago-Midway added some after spilling a plane onto a highway.

Doors to Automatic

1st Aug 2011, 18:37

I remember Chicago-Midway added some after spilling a plane onto a highway.

I believe it has already earned its keep too!

Teddy Robinson

1st Aug 2011, 19:58

long runway ... plane off the end. How ? Why ?

BobM2

1st Aug 2011, 20:36

long runway ... plane off the end. How ? Why ?

They could have achieved taxi speed well before the runway end, stowed reversers. F/O starts his after landing flow, selecting flaps up, then arriving at the turn-off point at runway end, find nil braking on a flooded, ungrooved runway... nose wheels just slide when turned. Capt reselects reverse, but too late to prevent over run. I've seen it happen...but on a -200 where much more effective reverse saved the day.

ross_M

1st Aug 2011, 21:16

gcap

1st Aug 2011, 21:29

I have considerable NG time as part of my 30,000+ hours. I will assume there is HUD installed. There were massive failures-mechanical-electronic-intellectual, or simply horrible pilot skills. The -800 is an easy dream to fly, and 7,500ft is more than enough for it in almost any circumstances. The HUD makes it easy, even in bad weather.

BobM2

1st Aug 2011, 21:39

It obviouly wasn't going fast 'cause it didn't go far...but down a steep 30ft embankment, through a fence, across the crown of a road...

dhardesthard

1st Aug 2011, 21:59

CAL 737s are not equipped with HUD.

Doors to Automatic

1st Aug 2011, 22:38

For info for non pilots reading the 738 can be stopped in approx 3000ft or 1000m after touchdown with flap 40 and autobrake max on a dry runway.

safetypee

2nd Aug 2011, 01:39

“For info for non pilots reading the 738 can be stopped in approx 3000ft or 1000m after touchdown with flap 40 and autobrake max on a dry runway.”

Plus some small print.

Providing the aircraft crosses the threshold at Vref at 50 ft, touches down within 1000 ft (HUD / Autoland distances are longer), at the assumed touchdown speed (Vref -7?), and that the spoilers / airbrake / reversers are deployed without delay (1sec buffer) and maximum braking used until stopped. And that the tyres and brakes are in reasonable condition, the runway surface and friction characteristics are as assumed by the performance chart, that the wind is as reported, and no doubt a few other minor items such as aircraft weight and all systems remain serviceable.

In practice, because the aircraft and flying techniques do not meet the accuracies above, an aircraft operation is planned to stop within a certification distance consisting of a ‘theoretical’ minimum (similar to the above) plus a factored safety margin. However, even this distance is often exceeded in overrun accidents due to a combination of factors, dominated by false belief, assumption, inappropriate action, or unknown / unreliable values.

“… long runway ... plane off the end. How ? Why ?” Not even a HUD will answer those questions.

rwyinsight

2nd Aug 2011, 03:12

Funny how everyone here is doing the "armchair" quarterback talking about what happened here. In the interview with the Captain he is talking about "saving lives"? Why didn't they do a go around and take a hold until the weather improved? I fly the 737-800 into 7000 foot runways and when it is wet we use Autobrake max and flaps 40. That equates to about a 138 knot ref speed roughly at 140,000 pound landing weight.

Lets wait and see the final report before jumping to conclusions!

If in doubt-Go Around! Thats what we train for in the "box" every 6 months!

ZQA297/30

2nd Aug 2011, 07:28

There is a big difference between dry stopping distance, wet stopping distance, and flooded runway stopping distance. When downpours happen, the runway can have areas of ponding where the water may be more than 1/4"deep.
All bets are off then as braking may be close to zero.
Ask any pilot who has experienced it, it feels like ice, like someone gave the aircraft a big push in the back.
Add to that, the particular runway has "good" areas where constant use has left a relatively clean surface, but the lesser used areas have a kind of moss coating that is greasy and slippery. Once off the beaten track so to speak, braking can be very variable. The far (eastern) end of R 06 does not see much use other than the odd taxiing aircraft after a long roll-out.
There have been several attempts at improving the runway surface in the past,and its 10 years since I was last there, but the policy used to be, do not stow (idle) reverse until down to a walking pace.
The last 1500' of the runway was not a place to try to slow from, say, 60kts. Depending on conditions you might have your hands full.
I used to operate there in L-1011s and the "relax" point was not until down to a walking pace with a decent bit of runway left!
Being a wee bit long or a wee bit fast was not an option.

fireflybob

2nd Aug 2011, 08:13

but the policy used to be, do not stow (idle) reverse until down to a walking pace.

used to be? I thought you were meant to do that anyway according to Boeing - that way you can always take reverse again without any delay.

ZQA297/30

2nd Aug 2011, 09:16

:ok:
Thanks FFBob, I said "used to be" because I passed my use-by-date some time ago and was not sure if things have changed!

Doors to Automatic

2nd Aug 2011, 10:07

Just to qualify my comments I did say "dry runway" and "stopped within" - the latter obviously assumes that the aircraft is on the ground first and travelling at the recommended speed! :ok:

fireflybob

2nd Aug 2011, 11:56

You do wonder sometimes if the landing performance criteria for landing on wet runways is really up to it if "average" pilots are taking it off the end.

I don't suppose somewhere like Georgetown would be up to providing up to date braking action reports for the runway, especially when wet.

On a slightly different tack, many years ago in the USA they put experienced pilots in the simulator ostensibly for some other reason but then gave them a major failure close to v1 on a field length limited runway. Something like 75 % went off piste at the end which led to the conclusion that maybe the take off performance criteria needed re-assessing (not sure whether they did).

Maybe the same applies to landing on slick runways. Personally I never relax till the machine is stopped.

Azumi

2nd Aug 2011, 14:42

In the image here. http://www.pprune.org/rumours-news/459037-caribbean-b738-georgetown-jul-30-2011-overran-runway-3.html#post6612041 For what it's worth, has anyone noticed and is it significant that the gouges in the grass show only TWO tracks for landing gear? Unless a main gear rolled over the nose gear track and obscured it, the nose gear wasn't on the ground at that point.

A Trini colleague walking past my desk pointed that out to me.

JanetFlight

2nd Aug 2011, 15:03

Azumi, the only two tracks are pretty correct IMHO cause they only depicted the 2 wheels on the right main landing gear.... the other 2 from the left one even the nose one, are out of photo range.
The nose ones due to the angle of the ravine, and according to some remaining speed, could be still out of ground contact (inertia too).

Doors to Automatic

2nd Aug 2011, 16:28

Yes I think it looks like that photo was zoomed in on on the tyre tracks of the RH MLG which makes it look like there were only two tyre tracks

lomapaseo

2nd Aug 2011, 17:25

I'm puzzled by all the interpretations here:confused:

In the recently referenced Photos of tire tracks, my first reaction was the RH gear in an obviously foreshorten photo (and not nose and single tire track)

I have seen the absence in other accidents of LH gear track where the gear was sheared off in the first ditch after it left the runway, so is this the case here ?

I have heard that slap retractions are automatic if the hydraulics are breached, could this be part of the explanation. It seems like all the info that is needed to investigate this accident is available on-site, so why are we guessing?

JW411

2nd Aug 2011, 17:58

Here is a Thought:

I did my initial DC-10 type rating with AA at DFW. My simulator instructor was a truly wonderful character called Frank Meyers. I think Frank first flew the DC-2 when he joined AA.

On an early exercise in the sim he had us taking off from a runway at Waco, Texas which exactly met Performance A requirements. He failed No.3 just before V1 and we both ended up just off the end of the runway.

"Right gentlemen" said Frank "Let us have a look at your seat position".

Now I tended to have my seat quite low and I sat a bit back from the rudder pedals (just like I did in a sailplane). Frank pointed out that in this position I could only get my ankle muscles on to the brake pedals whereas if I sat a bit higher and a bit closer, I could bear down with my thigh muscles etc and get much more pressure on to the brake pedals and much quicker.

I have to say that I did not really feel comfortable with having my seat in this new suggested position but it worked really well. I was easily able to stop next time we tried the Waco trick and from that time on I taught a hell of a lot of young men Frank's trick.

Can YOU apply FULL BRAKING in your present position?

FirstStep

2nd Aug 2011, 17:59

Lomapaseo, "Why are we guessing?".

Well, were bored and have nothing better to do.

OK, that's not entirely correct. Some people like to "stir the pot", aka Boeing vs Airbus, ect.

Seriously, by nature we are an inquisitive lot. We search for answers, and barring that, propose some hypotheses of our own. Any "official" report is y-e-a-r-s down the road, yet "we" as a group, often flying these exact planes, have concerns. After every accident and mishap I have seen here, I put, or at least try to put myself into the operating pilots position, and mentally try to see what I would do. "Cargo Fire" over the North Pacific ( maybe get more life insurance ), ect. And NO, I can't exactly replicate what the pilot's in question actually do, as I don't have all the "facts" as "they" saw them. Maybe "they" saw a TRW on the LOC, and decided to cut in short, and didn't give themselves time to get stabilized, ect. I'm not saying that happened here, by any means, but these type of things do happen, and often the pilots aren't around to give their side of the story. More often than not they're dead. So, even though there are a lot of factors that I can't take into consideration, I try at least to learn from the experiences of others, in my own way.
Also, there is a wealth of information and experience in the heads of those on this forum. Personal experience flying the same type of plane, sometimes the exact plane. Personal experience flying into a particular field, airspace, ect. You can learn a lot, I almost always do.
You can also be misled. There are those on this forum that have NO credible experience, yet speak as if they do. How can you tell?. Often, you can't. I suspect they're are "news" types that are looking for a sensational pilot perspective. They may get it from a 16 year old kid, who flies an X-box, with a Forum tag of "OldSalty727". If that name exists I apologise in advance...
These are just my thoughts on "why we guess".

virgin380

3rd Aug 2011, 00:10

Maybe there was a problem with flaps, maybe it was not going to full 40. so the crew may have attempted to cycle it without success and in the confusion while on final approach may have inadvertently left the lever in the "UP" position with the flaps stuck partially extended. On short final the flap may have slowly started to follow the lever position (UP). This may not have been realised and the pilot (unknowingly) compensated by adding more power to maintain his speed, or the auto thrust system automatically doing so. This would explain the assumed somewhat long and fast landing, and no "Config" warnings since flaps may have been still partially extended (20 or so). On rollout the flaps continued to retract finally reaching full up position just before running off the runway……..plausible, since an inexperienced co-pilot may not necessarly pick this up...Captain flying

Mad (Flt) Scientist

3rd Aug 2011, 01:27

That doesn't sound a very plausible scenario.

Firstly, it assumes a crew cycling the flaps while on approach - hardly conducive to a stabilized approach.

Secondly, if they were approaching with the flaps not fully extended and hoping that they would extend somehow, then they should have been considering the flaps failed landing distance - which since they overran it seems unlikely.

Had the scenario of flaps retracting during the final stages of the approach been possible, then there wouldn't have been a need to add power - if anything, the cleaned up config would need less power. It'd also be needing more AOA, though - something you'd think might be noticeable.

Depending on the system architecture, having the handle in the wrong position might be the input to a config warning, rather than the surface itself. Either are plausible. Would need to know the system specifics to know if thats a plausible suggestion.

nitpicker330

3rd Aug 2011, 08:59

Wrong, if you're on a stabilized approach with Flap 40 at about 130 kts and you run the Flaps up by mistake then you most certainly will need TOGA thrust to accelerate the Aircraft ASAP above the clean stall speed of around 180 kts, Even then it maybe be too late.:=

Boy there is some absolute rubbish being written in this thread.

F14

3rd Aug 2011, 09:01

As speculation, how about balked landing, followed by flaps selected up rather than F15. (is this a PtF recruiter?) Then a stop which sadly led to an over run?

I guess we have to wait for the preliminarily report. Nevertheless no fire and a good evacuation. Another good test of the B737-800 durability & survivability.

focault

3rd Aug 2011, 09:12

They could have achieved taxi speed well before the runway end, stowed reversers. F/O starts his after landing flow, selecting flaps up, then arriving at the turn-off point at runway end, find nil braking on a flooded, ungrooved runway... nose wheels just slide when turned. Capt reselects reverse, but too late to prevent over run. I've seen it happen...but on a -200 where much more effective reverse saved the day.

I think BobM2 got the point. If the runway is flooded and you misjudge your speed (at night could happen) you may not stop it even with 15 kts and once out of the concrete there is no more friction.

Magplug

3rd Aug 2011, 09:18

Landing on a 2200m runway even in pouring rain should not normally present a problem. This runway looks in good condition with no evidence of heavy rubber deposits that would degrade braking when wet.

If this upwind excursion was as the result of an unstable approach or a deep landing I would expect to see the aircraft come to rest in the landing configuration.... which it is not.

The flap/slat config seems to suggest that the after landing checks were initiated by the NHP abnormally early. I say 'abnormally' because normally there is no need to commence lights/flaps/apu etc. until the aircraft has vacated the runway. Here the checks have been started so early that by the time the excursion takes place the flaps & slats are stowed. The reversers deployed may simply be evidence of very late recognition of excess speed by the PF.

It seems highly likely given the LDA and the wet conditions that the crew would be planning to vacate 06 by turning left onto the parallel taxiway at the runway end.

It is quite possible that this was a normal approach and touchdown albeit in heavy rain.

With the crew already in the mindset of rolling to the end it is possible that the after landing checks were initiated prematurely, maybe even selecting both engines to Fwd Idle. As the runway end approached the speed was misjudged by the PF (PNF maybe still heads-down in checklist) and max manual braking and the reapplication of reverse were insufficient to prevent the excursion.

Henri737

3rd Aug 2011, 09:28

Or the aircraft broke, severing the flap controls, commanding flaps-up on electric hydraulics with the flaplever in 40 : lets wait for the investigation results.

nitpicker330

3rd Aug 2011, 09:56

Mate, Alternate Elec Flaps will only retract the trailing edge and not the leading edge. Have another look at the pictures.

The leading edges are retracted, it would have to have been via System B 3000 psi Hydraulic pressure and selection by the crew pre impact. That wouldn't have happened post impact when both Engines failed.

Some serious crap in here.:ugh::{

16024

3rd Aug 2011, 10:16

Electric flaps wouldn't go with generators lost, and wouldn't retract L/E devices anyway.

(And just realised Nitpicker beat me to it...)

However, as somebody suggested, with flap lever signal dirupted due to fuselage damage and engines spooling down, but still providing some hydraulic pressure...

J.O.

3rd Aug 2011, 10:36

What is being missed by some here is that any attempt to approach the ground with no (or minimal) flaps / slats would have resulted in a GPWS warning that is impossible to miss. All this talk of an inadvertant "miss" of the flaps is way off base, IMHO.

There will be lessons to learn from this accident. But is it really that hard to wait for some official information, rather than engaging in ridiculous speculation?

TacomaSailor

3rd Aug 2011, 19:00

Azumi

3rd Aug 2011, 22:40

While we're waiting on the actual report, this passenger reports Trinidad and Tobago's Newsday : newsday.co.tt : (http://newsday.co.tt/news/0,144914.html)

"Elias recalled two flight attendants being on their feet at the time the aircraft hit the runway. ... When the aircraft hit the ground, he said, the flight attendant who was in the aisle in front of him fell to the floor and the impact sent her sliding along the aisle. He does not know what happened to the other attendant."

At what point in a landing are attendants asked to take their seats? How soon after landing do they get back up?

Thanks for the perspective on the landing gear tracks.

Limer12345

4th Aug 2011, 03:21

All this hogwash speculation about flaps/slats/approach speeds/touchdown point etc......

All until the flight recorder shows that the aircraft was being operated by the 23 year old "ACE" in the RHS !!

And then we bitch and moan about the "paid RHS" seat jobs in Europe....and the infamous Indian fake CPLs etc....

Curry Goat

4th Aug 2011, 04:08

Two things of importance that a little birdie at the scene has told me.

1. Flap handle in the cockpit is selected to something other than up.

2. Aircraft left the paved surface doing at least 40 kts. This would rule out a previous theory of taxiing gone bad.

seckin

4th Aug 2011, 09:45

also look at the rudder position in the pictures before.. somebody was trying to make a desperate left turn..
also I believe the first pic in the following link was never posted. gives little more clue..
Accident: Caribbean B738 at Georgetown on Jul 30th 2011, overran runway (http://avherald.com/h?article=4407f71a&opt=0)

Shorrick Mk2

4th Aug 2011, 10:03

I measure approximately 45 feet from the lip at the top of the embankment down to where the ground levels off under the tail. I see no tracks down that embankment in the photos in message 75.

How fast would the aircraft have to have been moving (at the top of the embankment) to have enough inertia to continue off the top of the embankment so that both the nose gear and MLG remain off the ground, leaving no tracks, until the aircraft settled into it's final resting location?

The slope is to steep and the distance between the nosewheel and the MLG too long to expect nosewheel tracks down the embankment. The moment the nosewheel goes past the lip, the plane will drop onto the engine nacelles, like with a nosewheel collapse. If you look at the 3rd photo here (http://avherald.com/h?article=4407f71a&opt=0) you can see what looks like the track of the left nacelle dragging along the embankment (right behind the left stab - there's one guy clad in black walking down it). Once the nose will have impacted the ground below, it's quite likely that the MLG will not necessarily roll down the embankment, its task being taken over by the aft fuselage.

dhardesthard

4th Aug 2011, 10:11

The rudder position or the position of any other flight control surface with zero hydraulic pressure to the systems means nothing for obvious reasons. The DFDR will be the ONLY reliable source of information.:ugh::confused::=

WHBM

4th Aug 2011, 11:31

lomapaseo

4th Aug 2011, 12:25

Setting aside the aircraft handling aspects for a moment, the runway design looks notably poor, immediately at the end of the paved surface is an earth lip and a small drop (which has nevertheless broken the fuselage), and a vehicle track unnecessarily close to the runway end, followed by a flat grassed area out to the aerial array well beyond the aircraft, all withn the airfield fence. One day's work regrading with a bulldozer at the time of the runway construction, and some appropriate drainage, would have made a very adequate and level grassed overrun area. Quite what that earth lip achieves in civil engineering terms I cannot imagine.

Did anyone ever say "risk assessment" to the runway designers ?

Poor designed runway :confused:

I tend to look at anoother way. The airport designer initially looked at a much shorter runway with a nice flat overrun area as far as they could fill. Then along comes some big iron operators and says we will fly into your airport if you lengthen your runway as far as it can go.

So whose decision is it?

Is it poor design or poor decision making about the plane chosen to use the runway?

I've yet to see anything that regulates these kind of decisions in the mind of the pilots.

safetypee

4th Aug 2011, 12:35

Does anyone say “risk assessment” to the operating crews?

If a runway does not have a reasonable overrun safety area (length or condition), then perhaps the runway length available should be reduced in the pre landing (pre-operation) risk assessment.

simtronix

4th Aug 2011, 15:39

Accident: Caribbean B738 at Georgetown on Jul 30th 2011, overran runway (http://www.avherald.com/h?article=4407f71a&opt=0)

according to the latest update on the incident entry on Avherald:

Georgetown Airport's fire commander told the investigators that firefighters observed the aircraft as it approached but touched down only about half way down the runway abeam the terminal building with about 3000 feet of runway remaining. They needed to douse engine #2 (right hand engine) which was emitting smoke after the aircraft came to a stop.

Aviation sources said, the aircraft touched down with flaps fully extended (40 degrees).

hetfield

4th Aug 2011, 17:17

Aviation sources...

Who ist that?

Cleaners, Loaders, Security-Sheriffs...?

Henri737

4th Aug 2011, 18:57

quote=Mate, Alternate Elec Flaps will only retract the trailing edge and not the leading edge. Have another look at the pictures.=unquote

Completely missing the point.....

Che Guevara

4th Aug 2011, 19:41

The Flight Safety Foundation published a great presentation that may be useful for some to understand the factors involved with this accident; it can be found on their website or at the following Smart Cockpit link:

SmartCockpit - Airline training guides, Aviation, Operations, Safety (http://www.smartcockpit.com/pdf/flightops/humanfactors/17)

There are a couple more that you may be interested in:

SmartCockpit - Airline training guides, Aviation, Operations, Safety (http://www.smartcockpit.com/pdf/flightops/flyingtechnique/28)

SmartCockpit - Airline training guides, Aviation, Operations, Safety (http://www.smartcockpit.com/pdf/flightops/aerodynamics/44)

Just click on appropriate icon to open or download.

Cheers

hetfield

4th Aug 2011, 19:42

Not Found

The requested URL /.../flightops/.../Managing_Threats_and_Errors_ was not found on this server.

slf4life

4th Aug 2011, 20:03

Just want to express sympathy for the captain - can't imagine what's going thru his mind now. Regardless of the circumstances/causes/outcome, it happened on his 'watch' and must be hard on any commander.

Che Guevara

4th Aug 2011, 20:12

I have to agree with you there.

However, one of my problems after 31 years in the business is the lack of state of art letdown aids at some airports. Why doesn't the ILS work in Georgtown, why isn't there at least an RNAV approach there?
The Airlines are paying Landing Fees, so why not provide the facilities.

seckin

4th Aug 2011, 21:23

The rudder position or the position of any other flight control surface with zero hydraulic pressure to the systems means nothing for obvious reasons.
so the tracks going left are also meaningless.

nitpicker330

4th Aug 2011, 23:41

Henri737 severing the flap controls, commanding flaps-up on electric hydraulics with the flaplever in 40

what "point" am i missing?

Read my lips, YOU CANNOT RETRACT THE LEADING EDGE DEVICES USING THE ALTERNATE FLAP SYSTEM.

The system will not do it either intentionally or otherwise.

BobM2

5th Aug 2011, 02:37

Henri737
what "point" am i missing?

The point is that he is not talking about alternate flaps at all, but rather the break-up of the fuselage disrupting the mechanical linkage to the flap hydraulic power unit to command flaps up. If the crew did not select flaps up well prior to the overrun, there is no other way they could have been retracted. There must have been enough residual pressure for retraction.

NSEU

5th Aug 2011, 04:00

An inadvertent selection of flaps up on landing roll maybe ? That would stow the spoilers and make stopping far more difficult.

A FA friend mentioned, on B738s, once the emergency evacuation is activated,the flaps will retract to allow pax to use the overwing exits as an evacuation area...

Would someone please explain these strange undocumented features? My Boeing 737NG manuals have failed me. :hmm:

I've heard of spoiler blowdown on aircraft like 767's during overwing exit ops. Is this an option on the NG?

nitpicker330

5th Aug 2011, 04:12

BobM2 Re-read his post. he said commanding flaps-up on electric hydraulics with the flaplever in 40

The only Electric Hydraulic system on the 737 is the Alternate Flaps and these WILL NOT RETRACT THE LEADING EDGE DEVICES.

So, if the crash did cause the Alternate Flaps to run then ONLY the trailing edge devices would slowly retract using the Alternate and Electric Motor. But it is very slow, something like 3.5 minutes cycle time.

From the photos all the Flaps/Slats are fully retracted, the only way for this to occur is with normal HYD B power.

capish?

nitpicker330

5th Aug 2011, 04:22

This quote from the 737NG Operating Manual regarding the Flap system:--

Flap and Slat Sequencing
LE devices and TE flaps are normally extended and retracted by hydraulic power from system B………………etc

Alternate Extension
In the event that hydraulic system B fails, an alternate method of extending the LE devices and extending and retracting the TE flaps is provided.
The TE flaps can be operated electrically through the use of two alternate flap switches. The guarded ALTERNATE FLAPS master switch closes a flap bypass valve to prevent hydraulic lock of the flap drive unit and arms the alternate flaps position switch. The ALTERNATE FLAPS position switch controls an electric motor that extends or retracts the TE flaps. The switch must be held in the DOWN position until the flaps reach the desired position. No asymmetry or skew protection is provided through the alternate (electrical) flap drive system.
When using alternate flap extension the LE flaps and slats are driven to the full extended position using power from the standby hydraulic system. In this case the ALTERNATE FLAPS master switch energizes the standby pump and the ALTERNATE FLAPS position switch, held in the down position momentarily, fully extends the LE devices.

Note: The LE devices cannot be retracted by the standby hydraulic system.

nitpicker330

5th Aug 2011, 04:32

NSEU………….This is the Boeing 737NG PAX EVAC CHECKLIST:

The Flaps will not retract on any Boeing type, ever. The only thing is that on the 777-300 the inboard Spoilers retract to allow the Door 4 slide down the back of the wing. ( maybe on other types as well, but not the 737 )

737NG EVACUATION PROCEDURE

Both Captain and F/O complete their specific actions from RECALL (QRH Back Cover.2)
- Verify Flaps 40 (1) 1 - Verify parking brake set
- Select Speedbrake lever to down (2) - Engine start levers to CUT OFF
- Verify Flaps 40 - Select Pressurization Mode Selector to
Manual - Open the outflow valve (3) - Notify Tower (4)
(1) If time allows, verify that the flaps are 40 before the engine start levers are moved to CUTOFF.
(2) Speedbrakes are positioned down to prevent possible interference or injury to passengers evacuating through the overwing escape hatches
(3) Opening the outflow valve will ensure complete depressurization of the aircraft to allow opening of the escape hatches and doors.
(4) « MAYDAY MAYDAY MAYDAY XXX, EMERGENCY EVACUATION ON POSITION XXX »
2
Command evacuation with the PA:
«THIS IS AN EMERGENCY, EVACUATE THE AIRCRAFT USING ALL AVAILABLE EXITS » [called twice]
3
- Override and pull all ENGINE and APU fire switches
- Rotate and hold for 1 second engine or APU fire light which is illuminated
- Call « EVACUATION NON NORMAL CHECK-LIST »
- Take QRH and make ready EVACUATION check-list (5)
Time permitting, F/O reads the EVACUATION NNC. The Captain must respond to any items covered in his own areas of responsibility by repeating the response. The F/O will respond to any items which fall under his area of responsibility.
I.e. F/O reads: « PARKING BRAKE .... SET » Captain verifies and responds: «SET» When a pilot is incapacitated and an evacuation is necessary, the remaining pilot will take the QRH and execute each item.
4
After completion of the NNC the Captain will:
- Take a torch (and smoke hood if need be)
-Direct and assist passenger evacuation. Ensure all passengers and crew have evacuated the aircraft: using reasonable judgment and without undue danger, the Captain will check every row till the end of the cabin and assist immobilized passengers (if not yet done by the cabin crew), then evacuate using an aft exit
- Will assist passengers at the bottom of the left hand slides
After completion of the NNC the F/O will: - Take a torch (and smoke hood if need be) - Assist cabin crew as necessary to ensure
forward door(s) open and escape slide
activated. - Proceed to ground without delay. - Will assist passengers at the bottom of the
right hand slides
When a pilot is incapacitated and after completion of the NNC, the remaining pilot will ask cabin crew help to evacuate incapacitated pilot

hetfield

5th Aug 2011, 06:30

What could the possible reasons be for such a dramatic difference in landing speeds ?

Tankering...?

Henri737

5th Aug 2011, 11:20

OK, for the last time:

1. let's wait for the official investigation results.

2. about the flaps: I know how they work after 16.000 hrs 732,733,734, 737 and 738. What we don't know is what will happen and what the flapsystem can do on electric hydraulic pumps (engine's stopped so no engine-hydraulics)with the flaplever in 40 and you break the fwd fuselage in half: do you know? You will not find it in your cockpit companion or FCOM or in any other publication.

So it is not possible to predict or draw conclusions about aircraftsystems in an accident. This might go very different than you would expect so don't draw conclusions, let's wait for the accidentinvestigators.

dhardesthard

5th Aug 2011, 11:58

Henri737.........You meant 16,000 and not 16.000..!!:D:oh::=:rolleyes: I agree with the rest..!!:ok:

Expressflight

5th Aug 2011, 12:18

16.000 is correct on the continent of Europe.

Sciolistes

5th Aug 2011, 13:01

Henry,
What we don't know is what will happen and what the flapsystem can do on electric hydraulic pumps (engine's stopped so no engine-hydraulics)with the flaplever in 40 and you break the fwd fuselage in half: do you know?
At first I was going to respond dissing your post, but after some thought I see what you mean. We have no idea how the systems may have responded to short circuits, stretched cables and wot not during the accident. Any other possibility seems so unlikely that such an unusual configuration (look at the spoilers) would most probably be associated with the accident directly.

nitpicker330

5th Aug 2011, 13:15

I'd be very interested to see how the Alternate Flaps fluid could pressurize actuators backwards through a system designed to run only one way even if the fuselage broke up!!

The fluid from the standby reservoir pressurizes a dedicated line TO the Leading Edges and CANNOT suck them back up!!

Anyway...............I agree we should wait for the official report.:ok:

BobM2

5th Aug 2011, 13:23

BobM2 Re-read his post. he said

The only Electric Hydraulic system on the 737 is the Alternate Flaps and these WILL NOT RETRACT THE LEADING EDGE DEVICES.

WE ARE NOT TALKING ABOUT ALTERNATE FLAPS. Get that out of your head. Think about what powers B hydraulics.

The Ancient Geek

5th Aug 2011, 13:46

When are you stupid theorists going to accept that the flaps were used in the normal manner, F40 on approach then retracted under braking during the landing run. This is normal practice to avoid FOD damage to the flaps while taxiing, especially at 3rd world strips where taxiways are narrow and often littered with debris.

The cause of the accident is obvious, they landed fast and deep on a short strip. Sloppy airmanship, it happens regularly with the same result.
Simple rule for short strips:- Approach at the correct speed and if the wheels are not on the ground at the piano keys GO AROUND.

Henri737

5th Aug 2011, 17:30

Hi Nitpicker330,

I do not want to put you down in any way.
In training in the sim we all follow the QRH and get responses from the aircraftsystems as they should do. In real life time this can be totally different as in the books or sim. A heavy damaged aircraft can and will respont totally different than in the sim. The only way to know what was selected with the flaphandle is the flaphandle itself: the reaction of the system behind it depends on the integrety of the systems in the aircraft remains.

Really don't know what happended, investigation will reveal. The only thing I know is that a 800 or 900 on contaiminated runways are hard to slow down due to aquaplaning and a relatifly heavy aircraft on only 4 wheels. (like a 321)

apologize for my English grammar

Henri737

5th Aug 2011, 17:37

I mean slats and flaps could have gone up after the a/c came to rest uncommanded and no conclusions can be made looking at the pictures.

ZQA297/30

5th Aug 2011, 19:10

@The Ancient Greek.
While I hope you are wrong, I have to admit I think you have it right.

norbrook36

5th Aug 2011, 20:44

Allegedly... (http://www.kaieteurnewsonline.com/2011/08/05/pilot-apologises-for-error-in-judgement/)

nitpicker330

6th Aug 2011, 01:06

Whatever you think mate. :ok:

fdr

6th Aug 2011, 03:23

Should the fuselage have stayed in tact?....
May/may not be related but definitely worthy of scrutiny... Dateline, a current affairs program in Australia, did a story just last month about three other 737NG aircraft that have crashed on landing and broken up because of defective parts by a Boeing supplier which Boeing ignored even after two employees made them aware of the problems: "They say they couldn't keep quiet any longer over defective parts being made by a subcontractor, Ducommun, which they say were then allowed into 737 Next Generation planes between 1996 and 2004… some even had to be hammered into shape or packed with filler to make them fit."

See the story and read the transcript here: SBS Dateline | A Wing and a Prayer

The court case is still ongoing, and pretty much indicates the underlying attitude of Boeing to "excellence" of their product, instead of rectifying the fraudulent components and suing the supplier, they dismiss the 3 QA staff involved in uncovering the fraud and the safety issue.

So far there have been now 4 cases of B737NGs with these fraudulent parts that have broken up in a similar fashion. Coincidence? Perhaps, but the first fatality will come back to haunt Boeing I suspect.

Boeing's "Lipgloss on the Pig" re core values and ethics following their past ethical misbehaviour appears to be just that; gloss.

blakmax

6th Aug 2011, 13:50

Hi fdr

I saw that Dateline program and I was horrified to see that this current accident involved the same type of structural failure at the joints described. However, I disagree with your terminology of "Lip gloss on the pig". I suggest that the term "bovine excrement" should be applied to the quality management system used for these parts.

As SLF, I will in future try to avoid three rows of seats each side of these splice joints.

lomapaseo

6th Aug 2011, 15:43

As SLF, I will in future try to avoid three rows of seats each side of these splice joints.

good for you:ok:

and better for me, as I can select those seats that you leave open.

Considering that most survivable accidents that have a percentage of fatalities; those that are killed are because they are trapped in the aircraft long enough to be overcome by fire and smoke. While those that survive with only injuries are those that exit out a couple of feet drop through the breaks in the fuselage.

Of course I will admit that "if" there is no fire, most of the severe injuries are those that are exited out through the breaks in the fuselage.

Those are the breaks

and I will take my chances with living and hope to get seated next to one of those break joints :)

skol

8th Aug 2011, 02:22

dhardesthard

8th Aug 2011, 03:22

Due to high cost of fuel in Georgetown it is standard policy to tanker enough fuel to return to home base without refuelling. I doubt that this was a case of not enough fuel. However it may have made a difference if the A/C had only uplifted enough fuel in POS for a one way trip. Just speculating.;):suspect:

Escape Path

9th Aug 2011, 15:53

There's been a spate of similar accidents to this one over the last few years and I wonder how many of them are due to low fuel quantity, so many companies compelling and even forcing their pilots to operate with minimum fuel.

Arrive at destination with min. gas and it's hosing down, either divert quick-smart or take your chances in the rain.

Be interesting to know how much fuel was left at the end of the landing roll if I can call it that

Funny you say that. Remember the 737 that broke into three pieces upon landing around this time last year in a Colombian island? The same thing has been said; low fuel on board (no fire) and shooting the 3rd approach (SKSP alternates are Panama City and San Jose, Costa Rica). The Colombian CAA has said the investigation is complete and that they will be publishing the report soon. The accident was classified as CFIT due to approaching in really bad weather and as a contributing factor the "black hole approach"; loss of height appreciation due to lack of contrast.

misd-agin

9th Aug 2011, 20:24

dhardesthard -
Due to high cost of fuel in Georgetown it is standard policy to tanker enough fuel to return to home base without refuelling. I doubt that this was a case of not enough fuel. However it may have made a difference if the A/C had only uplifted enough fuel in POS for a one way trip. Just speculating.http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/wink2.gifhttp://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/cwm13.gif

With 154 passengers the amount of payload capacity available for 'tankering' fuel, before reaching max landing weight, is very limited.

I'd estimate the amount of fuel they could 'tanker/ferry' before reaching max landing weight is probably less than 6,000 lbs. Six thousand pounds is maybe 200'/65 meters)(?) extra landing roll.

Escape Velocity

9th Aug 2011, 22:53

Usually the alternate for GEO is POS, so they would have had to upload round-trip fuel anyway. The flight time POS-GEO is around an hour, so we're not talking a huge amount to tanker over required fuel. That said, they probably land close to or at max landing weight every time in GEO anyway with that pax load. We always did.

DownIn3Green

10th Aug 2011, 00:25

I can't believe it!!!

lomopaeso claims to be "able-bodied" and willing to jump out of any opening to escape, yet on the AA B-767 evacuation thread lomo professes to prefer to wait for the airstairs, a limo to the terminal, and a hot cuppa...give me a break...

dhardesthard

10th Aug 2011, 01:30

Looking at the arial shots of the crash site on avherald the A/C seems to be less than 200ft/65metres beyond the end of the paved circuit. This could have been the DIFFERENCE that I referred to because of the tankered fuel. Again just speculating. Using your figure of 6000 lbs, that is a lot of weight for a 737 that is close to MLW into Georgetown for that particular landing.

Teddy Robinson

10th Aug 2011, 03:00

whatever the landing weight, whatever the tanker fuel, if the landing is legal, schedulable with the normal landing factors applied, the role of the crew is to deliver the aircraft at the scheduled weight to the TDZ. If conditions are such that they are unable to achieve those conditions they divert.... or they run off the end of the tarmac as demonstrated.

skol

10th Aug 2011, 08:50

Correct there Teddy.
I was on a refresher course the other day where the matter of landing accidents was raised, and that these accidents are now more prevalent than controlled flight into terrain.

Our SOP's have gone exponential over the last 10 years but the latest amendment is to actually check the performance if the RWY LDA is less than a certain length, depending on type.

slf4life

10th Aug 2011, 16:09

GUYANA-Pilot error (http://caricomnewsnetwork.com/index.php?option=com_content&view=article&id=4743:guyana-pilot-error-suspected-in-caribbean-airlines-crash-wall-street-journal&catid=54:latest-news)

I know pilots 'are people too', but IF this is so, is it even possible for two airmen in what appears to be a fairly routine approach to not notice high speed and ultimately audible warnings? :confused: Surely there's more to it?

dhardesthard

10th Aug 2011, 17:38

How about a flap 30 landing after a long float resulting in a very late touchdown and subsequent overrun of the R/W. When the fuselage broke, a cable or rod activated the flaps and slats to retract.

Hotel Tango

10th Aug 2011, 18:33

IF it is pilot error what would interest me is why an experienced Captain could make such an error. Fatigue for instance?

Centaurus

11th Aug 2011, 11:41

but the latest amendment is to actually check the performance if the RWY LDA is less than a certain length, depending on type.

That means nothing in the real world and is there to cover management if lawyers get into the act. Most of the over-runs seen on accident reports published on Pprune were on runways that were well within legal performance limits. The problem has always been the press on regardless mentality of some pilots linked to reckless flying, overconfidence and occasionally ethnic culture that relies on a personal Deity to save the day.

lomapaseo

11th Aug 2011, 15:02

Centaurus

That means nothing in the real world and is there to cover management if lawyers get into the act. Most of the over-runs seen on accident reports published on PPRuNe were on runways that were well within legal performance limits. The problem has always been the press on regardless mentality of some pilots linked to reckless flying, overconfidence and occasionally ethnic culture that relies on a personal Deity to save the day.

A little harsh but correct.

It's a little like automation. It aint the tool that's bad it's the interface that needs work.

Nevertheless PPRuners have a way of polarizing around human perfection and fouled up technology.

Shore Guy

11th Aug 2011, 16:57

Something that is not normally trained for is a go-around after touchdown. One large American carrier is to begin training this on their 737 fleet. While not prohibited (most airlines teach only to stay on the ground after reverser deployment), very few pilots have been trained on this procedure and therefore not confident in doing it. Just think of how many overruns would have been eliminated with a go-around after touchdown.

One could never build performance charts for this event due to the number of variables (touchdown point, excess speed) so I am assuming some sort of guidelines are established beyond reversers deployed/stay on ground.

And, almost every overrun is preceded by a unstable approach.

GO AROUND!!!!

PEI_3721

11th Aug 2011, 17:18

The industry should be much more concerned about overrun accidents than they appear to be. There have been enough ‘non-fatal’ close calls to statistically warrant the real big-one.

Its good news that some parts of industry are taking this seriously, but is even more SOPs really the answer. Cross checking landing performance before each landing surely is a must before every landing – airmanship / professionalism. These checks are not just the cursory review of what the dispatch computer printout forecast, the task has to be an active assessment / reassessment of the actual conditions at the time of landing. Most operating regulations require this – “the Captain has to ensure that the conditions are sufficient for a safe landing”.
Checking the landing distance margin available (percentage of max allowed landing wt) provides a guide to the level of braking required. It can be a baseline on which to judge any tolerance to an error in runway conditions reporting – ‘runway is wet’, but the aircraft could still land if it were flooded (recent storm / poor drainage / slippery surface).

11th Aug 2011, 17:30

Just think of how many overruns would have been eliminated with a go-around after touchdown.

Or going around at 500' if not stable...... or, if you've not touched down by the end of the touchdown zone/markings...GO AROUND.

Don't ask for a "long landing" even if the runway is 4000m long...... it starts to establish in the mindset that it's "ok" and then you do it one day on a runway that isn't quite as long... and it's wet.... and ungrooved.... Why do people land long on purpose? To save 15 seconds :confused::confused:

It seems impossible to imagine that a crew flying a 4 year old modern jet transport could, apparently, make such a fundamental error as to not select flap/slat and then ignore all associated warnings resulting in an over-run. Incredible. The ONLY reason I can think of is fatigue or perilous fuel state.

Final report will be very interesting.

A4

dhardesthard

11th Aug 2011, 17:32

Attempting a take-off after touching down is going to be a can of worms. The decision has to be very critical. You are going to have to reset the flaps to a take-off setting, change the stabiliser setting, retract the speed brakes, set the new take-off power setting and now have new V1, VR, V2 etc speeds. I cannot see this being approved by the authorities.

misd-agin

11th Aug 2011, 18:13

dhardest - it's already approved and in the flight manuals/SOP's for every airliner I've flown(6+).

Rejected landing after touchdown, or similar wording, describes the procedure.

safelife

11th Aug 2011, 20:34

Try go around flap setting with Vref. Will work with almost any aircraft.

Henri737

11th Aug 2011, 20:39

Vref40=V2flaps15 so no problem

captjns

12th Aug 2011, 00:54

IF it is pilot error what would interest me is why an experienced Captain could make such an error. Fatigue for instance?

Because the mission has to be completed on the first go... ego... or not up to the task. The fatigue card is thrown out on the table way too many timesl.

KingChango

12th Aug 2011, 03:27

Flew through Kingston today, and i saw 2 Caribbean airlines 738 vacating rwy there. both times, i was paying attention on the flap setting before and while they were vacating the rwy. and ofcourse, both times these were fully retracted before even getting to the runway end.
maybe a little culture thing with them ? not speculating anything, but after reading this thread and getting all the input of retracting flaps and so and so, my best guess would be this. too early retraction. misjudging the roll out speed, and maybe skidding off.
thought to share the info, (making a new account just to reply)
sad :ok:

Hotel Tango

12th Aug 2011, 09:46

Captjns,

Because the mission has to be completed on the first go

What exactly do you mean by this?

or not up to the task.

Seems that if he's described as experienced that he must have been up to the task thousands of times before.

The fatigue card is thrown out on the table way too many timesl.

It is my opinion that fatigue factors are not taken seriously enough!

captjns

12th Aug 2011, 10:46

Well... "As to complete the mission on the first go." (AA1420 in Little Rock AK. AA in Kingston, Jamaica, Air India Express in Mangalore, India). Many accidents resulting in overruns or excursions have resulted in unstablized approaches. Would you agree if a missed approach or go-around had been executed I/A/W company SOPs these incidents may have been avoided? Let's face it sometimes egos take over where commen sense should.

As for "Not up to the task" There are training and checking departments within airlines that are inadequate within themselves that pass crewmembers' PCs and LPCs. (Take the crew of the Q400 in Buffalo for instance. Weak captain that was pushed through the system after a number of failures during his entire career even before joining the airlines. There was the F/O who was either unprepared, undertrained, or not of the proper mindset for flyng in cold weather adverse conditions). Also weak F/Os are afraid to speak up too. With that being said, they are part of the problem and not part of the solutions

As for fatigue card? Some crews who should have been responsible take required rest on layover don't. It's a fact of life of the airline industry.

Should a LOI to violate arise due to improper operations then the "Fatigue Card" is thown onto the table (EK flight from Melbourne that experienced a tail strike on deprature due to incorrect data being entered in the FMC.)

nitpicker330

12th Aug 2011, 11:41

Yes we are trained in Rejected Landings.

Quite simple really.

Apply TOGA ( t/o Warning will sound, ground spoilers retract and autobrakes disarm )
Leave the Flaps
Accelerate to VAPP ( Airbus ) VREF ( Boeing )
At VAPP/VREF and TOGA thrust Rotate
After Airborne and positive climb it becomes a normal Go Around ie "Go Around Flap 3" ( or 2 ) Followed by Gear up etc .....
Or for Boeing 737 "Go around Set thrust flap 15" Followed by Gear up etc...

However, once Reverse Thrust is applied a full stop is mandatory.

Huck

12th Aug 2011, 11:46

and occasionally ethnic culture that relies on a personal Deity to save the day.

You wouldn't happen to have any examples to back this up, would you?

captjns

12th Aug 2011, 12:44

Go-Around after Touchdown

Go-Around after Touchdown

If a go-around is initiated before touchdown and touchdown occurs, continue with normal go-around procedures. The F/D go-around mode will continue to provide go-around guidance commands throughout the maneuver.

If a go-around is initiated after touchdown but before thrust reverser selection, auto speedbrakes retract and autobrakes disarm as thrust levers are advanced. The F/D go-around mode will not be available until go-around is selected after becoming airborne.

Once reverse thrust is initiated following touchdown, a full stop landing must be made. If an engine stays in reverse, safe flight is not possible.

From the Boeing FCTM

kbrockman

12th Aug 2011, 13:59

Touch and Go with good old Sabena;
S30BBvxFXeM

Hotel Tango

12th Aug 2011, 18:23

Recognised Liege there.

Mikehotel152

12th Aug 2011, 21:12

I think the talk about training for go-arounds after touchdown is a slippery red herring. You need to look at the likely circumstances in which such a procedure might be performed. We're not talking about base training.

A pilot who has not performed a go-around despite an unstable approach in bad weather or who touches down long despite the runway being wet or of marginal length is already of a particular mindset. He or she will be desperate to finally get on the ground and will therefore almost certainly initiate maximum reverse thrust as soon as the main wheels touch down. If he or she is not of that mindset the chances are they will have already performed a go-around or baulked landing.

One only has to look at the incident in Mangalore in India to see the dangers of attempting a go-around after touchdown if reversers have been deployed.

dingy737

13th Aug 2011, 00:11

The aircraft was properly configured for a 30 flap landing!!! After impact the cable from the flap handle to actuator, did not break, but was under 7 times normal tension due to the bent fuselage, this resulted in an up selection to the actuator, somehow there was enough residual Hyd. psi to retract them. Beleive it!

DC-ATE

13th Aug 2011, 01:17

The aircraft was properly configured for a 30 flap landing!!!

Uh.....should not it have been a 40 Flap landing ?!?!

Ohhh the irony

13th Aug 2011, 02:14

It takes at least 30 seconds (closer to 35) to retract B738 flaps from 30 to up. That is with two engines at idle, two engine driven hydraulic pumps, two electric hydraulic pumps and an intact aircraft.

I guess all will be revealed.

dingy737

13th Aug 2011, 04:09

Dc-Ate, I agree that 40 flap would be my choice, but both 30 and 40 flap settings can accomplish the job safely with out any fuss. The point here was focused on earlier speculation about whether the were extended at all and the adjective "properly" configured was an attempt to convey that the aircraft flaps and slats were in a landing configuration at touch down as opposed to retracted at touched down or even extended for touch down then hurridely retracted for all types of posted theories.

framer

13th Aug 2011, 04:29

IF it is pilot error what would interest me is why an experienced Captain could make such an error. Fatigue for instance?

It is highly unlikely that the last error, or indeed the last few errors in the chain, weren't made by the pilots. The real improvements will be in identifying why these errors were made. ie did a poor culture exist within the pilot group with respect to briefing intentions should the landing not be working out? Was the authority gradient in the flightdeck appropriate? Was deviation from SOPs the norm? Do the SOP's preclude retracting flap while still on an active runway? Does the rostering system result in fatigue? Were the pilots likely to face negative feedback from management if they diverted or conducted a go-around? The answers to questions like that will describe to you why an experienced Captain could make such an error.

Or going around at 500' if not stable...... or, if you've not touched down by the end of the touchdown zone/markings...GO AROUND.

100% correct in my opinion.
Senior airline management need to be responsible for the cultivation of a culture in which this is the norm and deviating from it is seen as poor airmanship.

i saw 2 Caribbean airlines 738 vacating rwy there. both times, i was paying attention on the flap setting before and while they were vacating the rwy. and ofcourse, both times these were fully retracted before even getting to the runway end.

IMO this is going to be a major factor in the findings. Again....how can a companies SOP's be approved when they are flawed in this way? This incident may be the result of decisions made at a management level, should the regulator take some responsibility ? The head of operations?

After impact the cable from the flap handle to actuator, did not break, but was under 7 times normal tension due to the bent fuselage, this resulted in an up selection to the actuator, somehow there was enough residual Hyd. psi to retract them.
And you know this how? Are you sure it wasn't 8 times normal tension? How did you calibrate the tensiometer?

Maybe there was a problem with flaps, maybe it was not going to full 40. so the crew may have attempted to cycle it without success and in the confusion while on final approach may have inadvertently left the lever in the "UP" position with the flaps stuck partially extended. On short final the flap may have slowly started to follow the lever position (UP). This may not have been realised and the pilot (unknowingly) compensated by adding more power to maintain his speed, or the auto thrust system automatically doing so. This would explain the assumed somewhat long and fast landing
My Lord.....I sincerely hope that you are not an airline pilot. If that was the case, the Captain should surely be held responsible for making the decision to continue the approach with a flap problem into a short strip while 'confused'.

touched down only about half way down the runway abeam the terminal building with about 3000 feet of runway remaining.

Who would have thought? Instead of it being some freakish anomaly with flaps retracting by themselves , it's looking like a case of poor flight discipline. Who is responsible for the safety culture of an airline? I have my ideas on the answer to that.

As to the lack of flaps/slats.....perhaps that particular Captain retracted them at touchdown on short runways to dump the lift and, supposedly help with the stopping. Just a thought. I never did that but it WILL work.

Won't work very well in a 737-800 but anyway, if the SOP's don't stipulate where the after landing proceedure is to be commenced then there is a hole in the cheese just waiting to bite a crew.
A FA friend mentioned, on B738s, once the emergency evacuation is activated,the flaps will retract to allow pax to use the overwing exits as an evacuation area...
Your friend is wrong.

There are some posts on this thread that scare me a bit if they are made by airline pilots. Hopefully they are just teenage kids who love Microsoft FS and enjoy pretending to know things on this forum.
At the end of the day a combination of solid SOP's and the flight discipline to follow them and this over run would never have ocurred.
Framer

gottofly

13th Aug 2011, 06:34

once the a/c is on ground with reversers deployed,there is no question of trying to get airborne again.look what happened to AI Express at Mangalore.
I s there any talk about where the a/c touched down in this case?

Flaps 30 is good enough for a 7000ft rwy...its good enough for 6000ft even if its wet with good braking action....no sweat.

BOAC

13th Aug 2011, 07:19

The only 'fly in the ointment' for Dingy737 (#162) is that (OK, it did come from the WSJ, that fount of all that is knowledgeable and right) the flap lever was reportedly found in the up detent in the wreckage. That certainly is one heck of an 'up selection to the actuator':rolleyes:

Curry Goat

13th Aug 2011, 07:51

BOAC. The flap handle was found in a landing flap detent.

CG

BOAC

13th Aug 2011, 10:37

Thanks CG - that makes more sense. WSJ starring again in reporting! Link to WSJ in post #138 was my source.

sky jet

13th Aug 2011, 11:22

Finding the flap handle in the landing detent is inconclusive. If they ran the evacuation checklist the flaps would have been placed in the flap 40 detent. We will know soon enough where the flaps were or were not during the roll out. Speculation at this time is only that, speculation.

Jet

Doors to Automatic

13th Aug 2011, 11:55

Here is an example of a landing which should have been aborted. Note the application of flaps deep into the flare!

Scary Approach and Landning AeroGal B737-200 at Guayaquil Airport (Near crash) - YouTube

FalcoCharlie

13th Aug 2011, 12:12

The Aerogal video in youtube shows normal landing with landing flaps maybe 30 to 40 in the last seconds. Title of video is misleading too - nothing scary about it.

On the -200 we used to extend flaps from 30 to 40 after landing sometimes to help with the drag. Felt effective. I had never heard of retracting flaps while on landing roll until pprune...

Sqwak7700

13th Aug 2011, 14:10

nothing scary about it.

Really? I counted about a 12 second float, during which he added more flaps. Now THAT, I have never heard of. You really should not change configuration so close to the ground like that.

I had never heard of retracting flaps while on landing roll until pprune...

You never did your PPL? I thought it was standard to retract flaps on a short field landing in a small aircraft. I would not advise to get in the habit of doing this in an airliner though.

FalcoCharlie

13th Aug 2011, 15:18

Sorry cannot quote. Scary is relative. If you want scary extend the speedbrakes a few degrees to stop the float (not recommended). Of course I am certain nobody has done this, or landed with the flap load relief operating. These things never happen to us, only others far far away.

PPL? Too old to remember, however I seem to remember a discussion about instead of retracting the flaps after landing some people retracted the gear instead. Maybe that was the reason they didn't teach that.

Henri737

13th Aug 2011, 16:48

"On the -200 we used to extend flaps from 30 to 40 after landing sometimes to help with the drag. Felt effective."

No where to find in the Boeing 737-200 FCOM or FCTM.

Time for a serious talk with the chief-pilot.....:=

framer

13th Aug 2011, 22:04

Of course I am certain nobody has done this, or landed with the flap load relief operating. These things never happen to us, only others far far away.

Landed with the flap load relief operating? Mucked around with flap below 500 feet or on the runway? Geez no wonder you guys used to stack em more often in the old days. Never ever seen it or heard of it happening in the decade or so I've been with airlines. We would have gone around at 500ft if we were at the load relief speed. Things change a bit over the years by the looks.

misd-agin

14th Aug 2011, 16:17

gotofly -

Is there any talk about where the a/c touched down in this case?

Flaps 30 is good enough for a 7000ft rwy...its good enough for 6000ft even if its wet with good braking action....no sweat.
-----------------------------------------------------------------------

Non pilot eyewitnesses reported a long landing.

My perfromance charts say, even with Flaps 40, that 6000' will have weight restrictions if wet.

1500 hrs in the 737NG, most guys use 7000', or perhaps slightly, more runway, as the switch from Flaps 30 to Flaps 40.Wet runway and the switch is made for longer runways. Landing distance is part of the decision, the more critical factor is the reduced tendency to float with Flaps 40.

golfyankeesierra

14th Aug 2011, 20:05

I counted about a 12 second float, during which he added more flaps.
If I had to guess: flaps selected, but not extended because of flap load relief. When just before touch, speed bled off, flaps extended (just speculation).
BTW do they use FCOM's in South America?:}

framer

14th Aug 2011, 22:33

Flaps 30 is good enough for a 7000ft rwy...its good enough for 6000ft even if its wet with good braking action....no sweat.

I guess that would depend on the braking that was used considering that at Flap 30 and MLW Auto brake 2 will pull you up in 2370m nil wind. The runway is shorter than that so AB2 is obviously out if you're silly enough to be using Flap 30. Try AB3 Flap 30, if you do everything perfectly as by the book with nil wind it will pull you up 370m short of the end. How many people chew up 370m by carrying speed into the flare or having a touchdown located further in than 1000 foot? Plenty. If you were AB3 and flap 30 and touched down at the 2000ft markers for whatever reason, you will have to intervene with some heavy braking to avoid an overrun.
What if it was a 3 kt tail instead of nil wind? That increases all the distances by about 100m. Nah, Flap 30 in this situation would be a poor choice if you had no wind and were heavy.
Even Flap 40 AB2 will stop you only 30m short of the grass at MLW and put you 70m off the end if you have a 3kt tailwind.
My point? This needed to be a Flap 40 landing with AB3 as a minimum which will stop the aircraft in 1700m if everything goes well, it leaves you with about 500m for unforseen things like
1/ not crossing the threshold at exactly 50'
2/ not being exactly on speed
3/ not executing the perfect flare and touchdown
4/ the reported nil wind actually being a slight tailwind.
For all I know this crew did use Flap 40 and appropriate braking, but to say that Flap 30 is 'no sweat' is to ignore variables that you have limited control over, and to bank on everything going as planned.

PS all the above figures are derived from my books and the aircraft they apply to have 'short field performance'. I don't know if the accident aircraft did as well.
At max landing weight the aircraft legally requires a strip length of 1620m dry or 1860m wet (nil wind, standard day etc). If it's not short field performance then it'l need a fraction more.

dingy737

15th Aug 2011, 00:45

Question: If you depart from a 7400 ft runway at max Landing weight and loose an engine in a 737-800 can you return to land at that field.
The VREF speeds for max landing weight are aprox.,
Flaps 40= 142. Faps 30= 150 Flaps 15 = 158
The Boeing procedure for a single engine landing is to use flap 15. The Boeing Advisory landing distance for flap 15 one eng. inop. on a wet runway= 4888 feet, using max manual braking and max operative reverse thrust and of course touching down at the 1000 foot point.
I know of 2 such return to land events at that field at flaps 15 eng. out, still with no fuss, so flaps 30 is still more than adequate, and 40 being the best choice. So using flaps 30 are not to blame here.
Also the Boeing after landing procedure kicks in when clear of the runway which is when the flaps would be retracted, after speaking with a colleague at this airline in question this is also their SOP.
I do not understand this procedure of retracting flaps on the landing roll as they will transistion from the gratest drag posistion to the greatest lift posistion on its way to a fully stowed posistion and adversely affect the weight on wheels for proper braking.

westhawk

15th Aug 2011, 01:50

I do not understand this procedure of retracting flaps on the landing roll as they will transistion from the gratest drag posistion to the greatest lift posistion on its way to a fully stowed posistion and adversely affect the weight on wheels for proper braking.

The rest of your post makes sense to me but the above quoted text doesn't.

While full flaps produces more drag, more lift per unit of airspeed is produced as well. Note the lower Vref speeds associated with increased flaps setting. On jet transports, ground spoilers increase the weight on wheels and produce additional drag. This is far more effective at dumping lift than retracting flaps and adds drag instead of reducing it.

Retraction of flaps during the landing roll reduces the amount of lift produced at any given airspeed, thus increasing weight on wheels. It is an accepted and even manufacturer recommended technique to reduce landing roll distance on some light aircraft. Especially handy in bush flying.

I'm not aware of any jet transport aircraft where flap retraction during the landing roll is a recommended or approved action though. Ground spoilers are far more effective anyway and the danger of inadvertently selecting gear up instead of flaps up is mostly eliminated.

The Ancient Geek

15th Aug 2011, 01:57

I do not understand this procedure of retracting flaps on the landing roll as they will transistion from the gratest drag posistion to the greatest lift posistion on its way to a fully stowed posistion and adversely affect the weight on wheels for proper braking.

The objective on normal concrete or tarmac runways is to have the flaps stowed before turning onto a narrow taxiway where the engines may overhang the edges and foreign objects may be blown up, damaging the flaps. This is done late in the landing run at fairly low speed where any lift or drag considerations are minimal. Only a problem where taxiways are narrow and poorly laid out and more of a problem for turboprops than for jets.

Foreign object damage to flaps is a big problem at unmade airstrips where jets are unlikely to operate and pilots experienced in these conditions will have devoloped a habit of getting the flaps up as soon as reasonably practical to minimise the risk of damage.

framer

15th Aug 2011, 04:29

Question: If you depart from a 7400 ft runway at max Landing weight and loose an engine in a 737-800 can you return to land at that field.

Yes you can. In a perfect situation you will have plenty of room assuming max manual braking (about 1250m to stop from memory) but I think you already know that.

so flaps 30 is still more than adequate, and 40 being the best choice.
Depending on the braking scheduled IMO.
The s/e example is an emergency situation and therefore no factoring is required (as I am sure you know) .
Basically, by choosing Flap 30 (and I'm not saying this crew did), unless you select autobrake max your buffer for speed maintenance, threshold crossing height, touchdown point, float in the flare, tailwind etc is only 370m. Not enough in my opinion when simply selecting Flap 40 brings you an extra 200m of buffer. Of course it can be done at flap 30, but why would you?
If you applied max braking you could stop in 1000m....but why would you?
stack the deck in your favour and make sound choices, Flap 30 is not a sound choice on a runway 2200m long unless gusts are a factor IMO.

framer

15th Aug 2011, 04:40

The objective on normal concrete or tarmac runways is to have the flaps stowed before turning onto a narrow taxiway where the engines may overhang the edges and foreign objects may be blown up, damaging the flaps.
I guess we have a different definition of a 'normal concrete or tarmac runway' then.
In that scenario I would be briefing it before leaving cruise altitude and below 15kts before making the selection. But maybe that is because I have the luxury of operating into better strips and I don't understand how common it is to have taxiways like that as part of the route structure.

after speaking with a colleague at this airline in question this is also their SOP.

yet earlier a poster observed other aircraft from this carrier retracting the flaps on the runway subsequent to this accident. So is a finding going to be a culture within the pilot group to not follow SOP's? Poor safety culture? If so , I believe the only way around this is to find management level positions liable for the creating of acceptable safety cultures with pilot groups.Rather than the current situation where high level decision making degrades safety cultures.
Framer

dingy737

15th Aug 2011, 08:15

Thanks Westhawk on review you are correct. I was actually thinking of an aborted takeoff where the procedure is to extend the flaps to 40 after decelerating thru 60 knots and if done to soon at higher speeds, the flaps going from a takeoff posistion of 5 to 40 would increase lift and adversely affect braking. I must start posting in the day and not at 4 am.

WJAPilot

15th Aug 2011, 22:23

extending flaps further to 40 during a reject????

Who's SOP is that - its sure as heck not Boeings.

R u sure your not confusing it with the EVAC drill.

WJAP

framer

15th Aug 2011, 23:27

extending flaps further to 40 during a reject????

Who's SOP is that - its sure as heck not Boeings.

No idea? is it something that used to be done many moons ago?
Dingy737, you also stated;

The aircraft was properly configured for a 30 flap landing!!! After impact the cable from the flap handle to actuator, did not break, but was under 7 times normal tension due to the bent fuselage, this resulted in an up selection to the actuator, somehow there was enough residual Hyd. psi to retract them. Beleive it!

and have only joined up and posted on this particular thread, can I ask you if you are an engineer for this company or have some other sort of inside connection?
For me that would explain your in depth knowledge of the cable tension and also why you were emphatic that the crew used flap 30 very shortly the crash.
I understand if you would rather keep that information to yourself, just thought I'd ask in case you don't mind revealing how you know these things.

dingy737

16th Aug 2011, 15:55

As I remeber it for the 737 during an abort
F/O call 60 kts decelerating
Stop assured:
Captain:Reverse thrust to idle by taxi speed.
F/o: Lowers flaps to 40 degrees
The thinking was to have the flaps in the evacuation posistion in anticipation the abort may lead to an evac. I am not uptodate wasnt aware it was changed. but i do remember some f/o's being overly anxious to complete their drill and running the flaps to 40 while still above 60 kts and yes the evacuation drill call for the F/O to select flaps to 40 which would have already been done.
I have lots of friends in the region and i am just sharing the info i consider credible, currently in the sand.

WJAPilot

16th Aug 2011, 16:31

Dingy....

Sorry mate I think your confused... unless your company (which one was that) deviated from recommended boeing SOP and created your own.

The rejected takeoff drill says nothing of lowering flaps...in fact increasing flaps may even take more weight off the wheels and further inhibit braking.... as you recall at speeds less that 100kts the reverse thrust is less useful than the brakes.

The EVAC drill which is completely separate has the captain lower flaps to 40 to assist with over the wing egress..

Which model 37 are you referring to cause I've flown the classics and the NGs and neither have ever had anything your referring to.

I gotta call BS on your claim - either that or your memory is very incorrect.

WJP

dingy737

16th Aug 2011, 16:32

A 737 can come with hundeds of options all dependant on the operator.
While flying as a passenger on a Delta 738 I observed the de/anti icing procedure take place with the slats and flaps set for takeoff, on competion they were retracted for taxi. I asked the Captain about it and his reply was after the merger with northwest they adopted this procedure to have conformity acrooss the merger. I know several operators that still de-ice with flaps/slats retracted. So my question is, can an operator have its own procedure as long as Boeing sactions it?
The answer would have to be yes.
And if so what then are Boeing procedures? What you know as boeing procedures may just be your operators choice of options on a boeing aircraft.

dingy737

16th Aug 2011, 20:46

WJP the smartcockpit web site for B737NG-briefings displays the Ryanair RTO procedures which conflicts with yours, which require the Captain to select flaps to 40. Their procedure is to have the F/O do it.
Which is Boeings and how would you know? It is clear operators can make changes to boeings procedures. The procedure I quoted was for the F/O to run flaps to 40 when below 60 knots and stopping assured, I think the focus here is on stopping assured as in decelerating below 20 knots with 5000 feet of runway left , it was the crews call and the operators procedure not mine.

llnflder

16th Aug 2011, 23:16

our sops as well call for F/O to
-note reject speed
-Monitor braking speed brakes and reverse
-through 60 knots select flaps 40
and depressurize the Aircraft.

These I believe are closely worded to Boeing SOPs to keep things standard
for a Boeing 738 or NG
My two cents .

WJAPilot

16th Aug 2011, 23:17

llnfder what company is that may i ask.

The Boeing issued flight crew training manual for the 737-6,7,8,9 and BBJ
does not allude anywhere to the flaps being lowered during a reject...

why would you depresssurize the aircraft for a simple reject NOT leading to an evac?

Regards

WJP

dingy737

17th Aug 2011, 00:14

I beleive procedures are created from lessons learnt in previous incidents. Time is of the essence in most emergencies, rather than have several different rto drills why not have one that covers the worse case, its just being proactive and erring on the safe side. The 738 pressurizes the cabin on the take off roll, for passenger comfort. The drill as i knew it did involve selecting the outflow valve to manual and holding it until open to make sure their was no pressure differential. If the abort escalated to an evac. you would be well ahead of the game, if it did not no harm caused.
I was hoping that someone could post a Boeing offical link if it exist.
As for boeing manuals all operators will have Boeing issued manuals, with boeing printed on every page, the text and procedures will differ amongst operator as we have established.

dhardesthard

17th Aug 2011, 00:27

Looks like WJAPilot has been out voted..!!:ugh::rolleyes::=:D

Escape Path

17th Aug 2011, 03:23

BTW do they use FCOM's in South America?

Yes, we bloody do. What kind of a stupid, pointless, useless comment is that? :ugh:

The landing distance figures have been mentioned by a few people here, but I recall those are factored without the use of thrust reverser. So you would still have a slightly bigger margin in terms of distance before departing the runway, right?

Sciolistes

17th Aug 2011, 05:22

The Boeing issued flight crew training manual for the 737-6,7,8,9 and BBJ does not allude anywhere to the flaps being lowered during a reject...
No it doesn't with standard Boeing. But the FO selecting flap 40 used to be a recall item for the evacuation checklist with standard Boeing. I believe however, that different operators can have their own procedures approved which may vary greatly from the standard stuff.

I just took a look at the Smartcockit stuff. The Ryanair reject manouvre alludes the outdated procedure of the FO flap 40 recall item on the old Boeing evac checklist. It is dated 2008 when the standard SOPs changed and maybe Ryanair have also amended their procedure since then?

stator vane

17th Aug 2011, 07:43

hell, they change SOP's more often than i change socks!

WJAPilot

17th Aug 2011, 18:43

Ya lost all street credit when you used RYAN AIR as your example.

The drill to depressurize the cabin and lower flaps in all rejects is absurd...
but a point that will be lost by trying to argue the point.

The majority if not more than 90% of all rejects have nothing to do with requiring an evac.

But it doesn't matter either way... Ill never work for Ryan Air and won't have to worry about it.

Off to maui for the week enjoy chaps..

WJP

lederhosen

17th Aug 2011, 20:25

WJApilot I think you are the one losing street cred. making posts like your last one. Ryanair (not RYAN AIR) successfully operates around three times as many 737s as Westjet if that is who you work for. Those who have flown the 737 a bit longer remember various old procedures. Hopefully with experience SOPs are improved and we can lessen the risk of having our mistakes disected on PPRuNe including at least three recent landing accidents at night with the NG in central america / carribbean.

cuthbert31

26th Sep 2011, 21:51

Co-pilot reported to be 23/24 yrs old not much hours unless he has been crop-dusting from 14 which I doubt. Pilot was veteran

dhardesthard

27th Sep 2011, 04:00

How much is "not much hours"? How many hours is considered enough?
Is a "Veteran" someone who has been flying a long time, flying a long time in command, flying a long time on 737s or flying a long time in command of 737s?

Gooneyone

28th Sep 2011, 21:29

'Is a "Veteran" someone who has been flying a long time, flying a long time in command, flying a long time on 737s or flying a long time in command of 737s?'

Isn't the answer yes to almost all of the above if he is a "Veteran":ugh::ugh::ugh::ugh:

dhardesthard

29th Sep 2011, 01:09

Veteran could be in aviation a long time but new to the left seat or new to the type or new to the route if he was on another fleet or because of Sim training position has more desk time than plane time. Without going into detail I do not consider the individual to be a Veteran, that is not to say that he was incompetent.

Limer12345

9th Oct 2011, 12:16

Has there been any update on the probable cause of the accident??

Lots of speculation here...the terms "veteran" and "experience" are all relative terms....

Every CAL pilot would have been "GEO hardened" from his/her early days on the RHS....I seriously doubt LHS experience was a factor here.

Complacency/fatigue/training/SOPs perhaps.....now that's a whole different kettle of fish..

Dream Land

9th Oct 2011, 17:26

norbrook36

10th Oct 2011, 22:49

Well it doesn't really sound that complicated, from the reports already available, the crew apparently was landing in some pretty rough conditions, shortish runway, heavy rain, and I would assume a contaminated runway, add to that a long landing, recipe for disaster.

Not to be pedantic but the conditions were not exactly "pretty rough". No rain or wind at the time and visibility >5km. It's possible that your "long landing" could have been VERY long.

Dream Land

12th Oct 2011, 16:35

Trinidadian pilot Fareed Dean, who crash-landed an Air Caribbean Boeing 737-800 at the Cheddi Jagan International Airport early yesterday morning, told relatives in Trinidad that poor visibility due to heavy rainfall resulted in the aircraft over-shooting the runway, but insisted he did his best to prevent the loss of lives. I was reading the newspaper reports which quoted the captain about the heavy rain, there was also a comment about poor runway lighting which is not uncommon in places like this.

So, from what I read so far:

Possible contaminated runway, hydroplaning?

Runway not too long.

Poor vis due to rain showers.

Not so good field lighting.

Full aircraft with extra fuel for the tankering.

And how much rest did the crew have that day?

This is rough conditions to me.

ws737

13th Oct 2011, 01:24

was reading the newspaper reports which quoted the captain about the heavy rain, there was also a comment about poor runway lighting which is not uncommon in places like this.

So, from what I read so far:

Possible contaminated runway, hydroplaning?

Runway not too long.

Poor vis due to rain showers.

Not so good field lighting.

Full aircraft with extra fuel for the tankering.

And how much rest did the crew have that day?

This is rough conditions to me.

I flew for CAL all last winter on the 800.

Contaminated runway hydroplaning? Possible, but not that likely,the runway is almost brand new, virtually no rubber in the touchdown zone, in excellent condition and it sheds water beautifully because it is crowned and grooved. I landed in possibly one of the worst rainshowers in my career on that runway, at night, same flight number even...most likely at the same weight as this AC and had excellent braking.

Runway not too long-7400 ft...read first paragraph and go to the B737-800 braking charts and see where you sit..shouldn't have been a problem

Poor visibility-rainshowers, the approach they were on is an RNAV/VNAV 06 that puts you where you need to be, when you need to be there if flown properly...things don't always go as planned as we all know

Not so good field lighting-It's a black hole approach over the jungle, RNAV/VNAV puts you right in the slot and there was a functioning..(when I was there)..VASIS system that was the correct eye to wheel height for the 800.

Full aircraft with tankered fuel-It's a 50 min flight..with tankered fuel for the return, alt, everything in, we only had about 8000kgs, max, on that flight

How much crew rest- Anybodies guess but that flight was a continuous duty overnight and it was the only flight they would have done that day unless something very unusual happened

These would not be considered rough conditions by myself or any of the crews flying down there then, or now. I don't pretend to know what happened, I've tried to get more information but haven't come up with much.

My two cents