FR 737 taxis with towbar stuck under engine

[kgbbristol]

From Airlive:The Boeing 737-800, with registration 9H-QAH, was scheduled to depart as flight FR2907 from Frankfurt International Airport to Puerto del Rosario Airport on 17th December.

The tow bar remained attached below the engine until the pilots stopped taxiing.

In the event, sparks came out of the engine caused by the friction of the tow bar. In the video shared on the internet, sparks emanating could be seen.

I can't post links - see Airlive or search user BaileyB92043349 on Twitter

[HOVIS]

Misleading headline.
Looks more like its hit the towbar with the engine and dragged it along.
Tow bars are not 'attached' to engines.


Thread title edited,
Senior Pilot

[Pilot DAR]

https://www.airlive.net/incident-a-ryanair-boeing-737-800-began-to-taxi-with-its-tow-bar-still-attached/

It looks more like the plane was taxied over the towbar, and snagged it, then taking it for a trip down the taxiway.

[JanetFlight]

https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/1024x768/img_20211219_wa0009_709df164e252077fb8ab8cf11a1517f0327eafef .jpg
https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/768x1024/img_20211219_wa0013_ef47014d97120cc5428153034315177206812a43 .jpg
https://cimg4.ibsrv.net/gimg/pprune.org-vbulletin/1024x768/img_20211219_wa0021_b73f1cfaf05c6a14b96f501cd768e34cd701f3cd .jpg

[Magplug]

When a tow-bar is attached to the nosewheel of a 737 it is pretty much hidden from the flight crew. We are at the mercy of so many other people, trusting that they do their jobs correctly. I have to admit that I take the 'pin & wave-off' at face value without actually identifying the individual elements as they are moved away from the aircraft. It does seem pretty unlikely that the groundcrew would forget to remove the tow-bar after pushback.... but were they distracted by something at a critical moment?

When all is said and done I cannot imagine the feedback through the tiller is something you could possibly miss on taxy as the tow-bar jack-knifes and breaks off the engagement lugs.

RYR pilots always seem to be in a hurry.... Or is that my imagination?

[A4]

Simple cure. DO NOT start the after start checklist until you have watched the tug, tow bar, man and pin clear the aircraft and safely cross "over the line" back into stand area. Verbalise it for the benefit of your colleague and the CVR. The taxi way is then yours and unobstructed - the after starts can then be done in the knowledge there's no-one or any equipment close to the aircraft.....because you weren't heads down doing checks when you need to be heads up watching the ground crew and equipment clear the aircraft. That's worked for 20+ years for me............

A4

[CW247]

How we got to 2021 without external cameras on a $100 million dollar jet but 8 on a $100k Tesla, I will never know.

[ICEHOUSES]

I thought Ryanair had bulletproof SOP’S and procedures or is this an experience level problem at this airline.

[DaveReidUK]

When all is said and done I cannot imagine the feedback through the tiller is something you could possibly miss on taxy as the tow-bar jack-knifes and breaks off the engagement lugs.

I haven't seen any photos yet showing either the business end of the towbar or the NLG. It will be interesting to see the extent of the damage to the latter, given that the aircraft was able to position from FRA to Berlin the following evening, presumably sporting a large quantity of speed tape under the cowl.

[Nightstop]

Was the aircraft departing from a self-manoeuvring Stand? I wouldn’t be surprised if the towbar was collected from an adjacent Stand while taxiing out at a brisk pace.

[DaveReidUK]

Looks like it pushed from D4 or D4A, facing west. The aircraft appears to have come to a stop roughly abeam C14.

[Nightstop]

Oh OK. I still think this towbar was not the one that was used during their own pushback, more likely collected en-route. TBA of course.

[Pilot DAR]

more likely collected en-route.

That was my thought as a possibility. If so, the towbar certainly should not have been where it was, and the crew should have been confirming that their taxi path was clear as they proceeded.

[42psi]

I'm aware of an incident a few years (not a 737) where the towbar ended up in almost the same position.

In that case the error was spotted and the aircraft stopped before being struck by the towbar.

The sequence was, after completing the push:

Bar disconnected from tug.
Tug moves forward to leave room to disconnected the bar from nose gear.
Bar is disconnected from nose gear.
Bar is pulled forward ready to re-attach to the tug
Before doing this the headset person removes bypass pin & unplug headset.
​​​​​​ As the push had been longer than normal it was too far for the headset person to walk back to stand.
Headset person entered tug as passenger and they returned to stand where pin/flag were displayed.
Inexplicably they forgot to reattach the bar to the tug before driving off.
​​​​​​ It was thought that the longer non standard push caused a distraction and they were uncomfortably exposed being a considerable distance from the stand with another section of twy to cross before reaching safety.
They were eager to return quickly from an area they felt exposed/unsafe.
As the aircraft started to move it commenced a left turn towards the adjacent runway holding point.
The error was spotted and the aircraft stopped just before the bar would have struck the right engine.

I suspect something similar may well have happened here.

I note that the towbar head is under the engine, it would seem unlikely it was still attached to the nose gear at the time of txy?

I'd guess either left in error or not correctly attached to tug when it moved off.

[HOVIS]

Ive seen tow bar pins get bounced out of the tug's towing lugs before, sending the towbar careering across the taxiway. Tug crew non the wiser. I suppose its possible, at night for the same to happen but snag a 737 on the way.

[kriskross]

I know on my old Company that both pilots had to see the tow bar clear of the aircraft and away before the after starts could be ..er...started.

[Tom Sawyer]

No idea how this happened, but seems they took the towbar with them for a fair old distance - https://www.youtube.com/watch?v=4zZZXj_wPC8 . As someone suggested above, it looks like they collected it whilst taxying?

[CW247]

Collected whilst taxying most likely, but whether they collected it because of a taxying error or because ground crew didn't position it properly we don't know yet.

[Shackeng]

Do Ryanair crew have bonus/penalties for being on time/delayed?

[Uplinker]

Very odd.

If the bar was someone else's left on the taxiway, the ground crew would not have released the aircraft to taxi, or the taxiing crew would have seen it and stopped, so it can't have been that.

Had the bar been left attached to the nose-gear, there is a frangible link that would have broken when they moved forward, releasing the bar and they might then have run over it with their engine. So that would be a ground-crew issue, but also the flight-deck, since they wouldn't have seen the tow-bar attached to the tug to confirm "clear".

Third possibility is that the bar was removed normally and seen as "clear" but it then became detached from the tug and rolled away, coming to rest on the RHS of the aircraft with nobody seeing or realising. Or maybe the ground crew did wave but both pilots were looking forwards by then.

We had an SOP to each have a good proper look round to confirm "clear left" and "clear right" before moving, but on many types, you cannot see your own engines from the flight deck - unless you both laboriously unstrap and stick your heads out of the DV windows.

[flyfan]

Simple cure. DO NOT start the after start checklist until you have watched the tug, tow bar, man and pin clear the aircraft and safely cross "over the line" back into stand area. Verbalise it for the benefit of your colleague and the CVR. The taxi way is then yours and unobstructed - the after starts can then be done in the knowledge there's no-one or any equipment close to the aircraft.....because you weren't heads down doing checks when you need to be heads up watching the ground crew and equipment clear the aircraft. That's worked for 20+ years for me............

A4

That's more or less what the company SOP says. Only thing that can/should be done before that: Generators on bus, APU off. Everything else only after receiving the clear signal.

[DaveReidUK]

Collected whilst taxying most likely, but whether they collected it because of a taxying error or because ground crew didn't position it properly we don't know yet.

The ground track looks pretty unexceptionable, so a taxy error looks unlikely.

The incident took place about an hour before sunrise at FRA.

[SWBKCB]

Ive seen tow bar pins get bounced out of the tug's towing lugs before, sending the towbar careering across the taxiway. Tug crew non the wiser. I suppose its possible, at night for the same to happen but snag a 737 on the way.

This looks like the most likely suggestion so far. Totally unrelated tug is bobbing along, the tow bar seperates and it goes off on its own merry way, collecting the passing Ryanair

[Jump Complete]

I once saw a tow-bar, still attached to the tug, being dragged along inverted, sending up sparks with the wheels in the air, at Manchester as we taxied in. They were hooning round the corner so fast that it flipped over. The Captain, being something of a character, took over the radio to report it, leaving no doubt of his opinion of the tug-driver.

[EcamSurprise]

I'm aware of an incident a few years (not a 737) where the towbar ended up in almost the same position.

In that case the error was spotted and the aircraft stopped before being struck by the towbar.

The sequence was, after completing the push:

Bar disconnected from tug.
Tug moves forward to leave room to disconnected the bar from nose gear.
Bar is disconnected from nose gear.
Bar is pulled forward ready to re-attach to the tug
Before doing this the headset person removes bypass pin & unplug headset.
​​​​​​ As the push had been longer than normal it was too far for the headset person to walk back to stand.
Headset person entered tug as passenger and they returned to stand where pin/flag were displayed.
Inexplicably they forgot to reattach the bar to the tug before driving off.
​​​​​​ It was thought that the longer non standard push caused a distraction and they were uncomfortably exposed being a considerable distance from the stand with another section of twy to cross before reaching safety.
They were eager to return quickly from an area they felt exposed/unsafe.
As the aircraft started to move it commenced a left turn towards the adjacent runway holding point.
The error was spotted and the aircraft stopped just before the bar would have struck the right engine.

I suspect something similar may well have happened here.

I note that the towbar head is under the engine, it would seem unlikely it was still attached to the nose gear at the time of txy?

I'd guess either left in error or not correctly attached to tug when it moved off.

That wasn’t a 340 was it? I’ve watched exactly the same thing happen to a 340 in VIE. It was only because if my radio call that one of their right engines didn’t go into the tow bar.

[FlightDetent]

As in 'Saab 340', right?

[WHBM]

Maybe if the driver of the ramp vehicle could have been fully occupied radio-ing for Ryanair to stop, or to be contacted to stop, rather than seeking their 30+ seconds of fame by videoing it all on their phone to be posted on YouTube, whilst driving along (contravention of their ramp driving permit, surely), they could have been pulled up quicker.

[DaveReidUK]

As in 'Saab 340', right?

We'd have to know which one of their right engines the OP was referring to, before deciding that. :O

[GcitoG]

That's more or less what the company SOP says. Only thing that can/should be done before that: Generators on bus, APU off. Everything else only after receiving the clear signal.

At my company, we get the clear from ground crew (we check for safety pin / towbar attached to tug / wave), do our flow and then after start CL.

[hans brinker]

I do the After Start after the engine is started, that way I am ready to taxi and can look outside for the clear signal. I do not release the brake until after I have received a clear signal and counted 123, clear (tug, tow bar, pin). Whatever trigger you use to make sure it is okay to continue works, but I believe the best triggers are related directly, and waiting for the ground crew to be gone before you do an unrelated checklist doesn't help. Worked for me for the last 20 years, and in compliance with SOP.

[Magplug]

1,2,3 ???? Tugs? Towbar-less Tugs? Remote control pushbacks? No pushback?

How many SOPs do you have exactly ? :rolleyes:

The ramp areas at FRA are VERY well floodlit. Pretty much every aviation journal I look at online is saying that the aircraft taxied with the towbar still attached rather than picking it up during the taxy.

[DaveReidUK]

Pretty much every aviation journal I look at online is saying that the aircraft taxied with the towbar still attached rather than picking it up during the taxy.

Though most journals tend to parrot each other, so the sheer number of reports isn't necessarily a guide to their accuracy.

I'd want to see a photo of the business end of the towbar and the NLG pickups before reaching any conclusions - anyone seen one?

[hans brinker]

1,2,3 ???? Tugs? Towbar-less Tugs? Remote control pushbacks? No pushback?

How many SOPs do you have exactly ? :rolleyes:

1, because everywhere I fly we have a push with a towbar. Pretty sure that if I ever have to get used to doing supertug, I can adjust the math.

[richardthethird]

Ryanair. Say no more....

[DaveReidUK]

No need for an investigation, then ... ?

[richardthethird]

Not in my book!

[Magplug]

1, because everywhere I fly we have a push with a towbar. Pretty sure that if I ever have to get used to doing supertug, I can adjust the math.
That's half the problem..... You only fly to a limited number of destinations. Every company is obliged to audit their own ground handlers at each station or the handling agents retained at that destination. Different aircraft have different SOPs and different requirements for verbal communications with the ground. It needs to be kept as standard as possible and as simple as possible but unfortunately a lot of places just like doing their own thing regardless of the consequences (ever been to JFK?).

Ready to push should mean 'ready in all respects now' not simply 'We are all here'.
'Clear to pressurise' - Do modern day Boeings still need this or is it a holdover from the past?
Brakes ON / Brakes OFF - In widespread use but safe? Better.... 'Brakes released / Brakes set to park'

And that's even before we get to safe communications for De-Icing or Ground air starts !

[Australopithecus]

That's half the problem..... You only fly to a limited number of destinations. Every company is obliged to audit their own ground handlers at each station or the handling agents retained at that destination. Different aircraft have different SOPs and different requirements for verbal communications with the ground. It needs to be kept as standard as possible and as simple as possible but unfortunately a lot of places just like doing their own thing regardless of the consequences (ever been to JFK?).

Ready to push should mean 'ready in all respects now' not simply 'We are all here'.
'Clear to pressurise' - Do modern day Boeings still need this or is it a holdover from the past?
Brakes ON / Brakes OFF - In widespread use but safe? Better.... 'Brakes released / Brakes set to park'

And that's even before we get to safe communications for De-Icing or Ground air starts !

I don’t know if modern day Boeings still require a clearance to pressurise, but 737s do.

[hans brinker]

That's half the problem..... You only fly to a limited number of destinations. Every company is obliged to audit their own ground handlers at each station or the handling agents retained at that destination. Different aircraft have different SOPs and different requirements for verbal communications with the ground. It needs to be kept as standard as possible and as simple as possible but unfortunately a lot of places just like doing their own thing regardless of the consequences (ever been to JFK?).

Ready to push should mean 'ready in all respects now' not simply 'We are all here'.
'Clear to pressurise' - Do modern day Boeings still need this or is it a holdover from the past?
Brakes ON / Brakes OFF - In widespread use but safe? Better.... 'Brakes released / Brakes set to park'

And that's even before we get to safe communications for De-Icing or Ground air starts !
About 70 destinations in 18 countries in my current airline, and yes been to JFK, LGA, EWR, LHR, AMS, MAD, BCN and about 400 more.... The reply I gave was all about having SOP use the appropriate trigger, and I feel using the after start as a trigger to look for the tow bar isn't the best thing. I think releasing the parking brake should be the trigger to make sure both of you have confirmed that you are clear to taxi (nothing attached to the aircraft, taxi instructions received, both know where we are going). Nothing to do with ground communications.

[G-ARZG]

Maybe if the driver of the ramp vehicle could have been fully occupied radio-ing for Ryanair to stop, or to be contacted to stop, rather than seeking their 30+ seconds of fame by videoing it all on their phone to be posted on YouTube, whilst driving along (contravention of their ramp driving permit, surely), they could have been pulled up quicker.

The incident was brought to an end (a head?) when a ramp worker, maybe even the one filming, managed to attract the attention of the crew who stopped the aircraft - earning their '15 minutes of fame'?

[70 Mustang]

I don’t know if modern day Boeings still require a clearance to pressurise, but 737s do.

I’ve flown most models of the 737 in 6 different airlines in 4 different countries and never once have I ever seen “cleared to pressurize”

[Australopithecus]

Well, I have flown most too, from the 200 basic on up to the -800. Ground clearance to pressurise hydraulics became a procedure in the mid 90’s and remains with us still.

[70 Mustang]

With bypass pin in, are not the hydraulics blocked from the nose gear? They did show us the pins as they left.
if that’s what you meant by being cleared to pressurize, okay. I get that.

A few times, even when seeing the pin, we still couldn’t steer the aircraft.

GENERATORS 1 …… ON
APU switch ................. As required
START SWITCHES...... CONT
PROBE HEAT switches ......... ON
WING ANTI–ICE switch................... As required
ENGINE ANTI–ICE switches ................. As required
PACK switches............................. AUTO
ISOLATION VALVE switch........... AUTO
APU BLEED air switch ..................OFF
FLAPS................... ___REQUIRED, ___SELECTED, GREEN LIGHT
Flap position indicator and FLAP lever - Set for takeoff

[Brian Pern]

With bypass pin in, are not the hydraulics blocked from the nose gear? They did show us the pins as they left.
if that’s what you meant by being cleared to pressurize, okay. I get that.

FLAPS................... ___REQUIRED, ___SELECTED, GREEN LIGHT
Flap position indicator and FLAP lever - Set for takeoff
Three aspects of the Flap selection must be confirmed by the Captain in response to the Challenge “Flaps”.
“______ Required”

These look suspiciously like Ryanair SOP's. I say this, because having been around the block a few times, I have never come across it, the only time is with ex Ryanair crew.

But I digress, back to the Pressurise Question, I have always asked the ground crew 'are we clear to pressurise Hydraulics' , they go on just before push and off as part of the engine shutdown, I know this is not fashionable, certainly in the above mentioned company, but you really don't want Skydrol at 3000psi hitting you on the walk round, leaks are bad enough, worse under pressure.

But what do I know TRE, over 30 years in Jurassic's, Classic's and NG's (mainly BBJ) visiting several hundred airports in process.

Until we really know what happened, I will reserve placing blame on the crew, it is interesting there is a video though, I would have though the ground crew would be trying to get the cockpits attention somehow.

[Locked door]

The “clear to pressurise” is more about the sudden movement of parts of the aircraft than about leaks.

Before you are cleared to pressurise all flight controls will be checked clear of obstruction (fuel truck, de ice rig etc), no personnel near gear doors or under the A/C and the steering bypass pin inserted. That way if something moves suddenly on application of hydraulic pressure no one will get hurt or no damage will occur. Hopefully.

[Nightstop]

A few times, even when seeing the pin, we still couldn’t steer the aircraft.

The 737 NWS bypass pin is made of two concentric metal tubes, the outer of which has the flag attached. In an internal bypass pin failure, it is possible for the outer tube with flag to be removed but inner tube to be left behind and still engaged. The result? Impossible to use the NWS for directional control. Has happened to me.

[HOVIS]

I’ve flown most models of the 737 in 6 different airlines in 4 different countries and never once have I ever seen “cleared to pressurize”
It's been standard procedure on all the Boeings I've been involved with since the early 1980s.
Main reason, to ensure we don't pressurise the steering system with a tow bar attached and no lock out pin fitted. As explained above, other reasons exist too.

[Krystal n chips]

It's been standard procedure on all the Boeings I've been involved with since the early 1980s.
Main reason, to ensure we don't pressurise the steering system with a tow bar attached and no lock out pin fitted. As explained above, other reasons exist too.

Notably the inboard Krueger flaps on the 737 .

[DaveReidUK]

A steering input that succeeds in turning the NLG when the towbar is detached from the tug, but still attached to the aircraft, can have potentially fatal results.

[Elle Overdee]

AAIB Bulletin 01/2022 has a report on a similar incident from last June. (AAIB 27402).
Human factors/ground crew coordination.

[DCS99]

Zurich has been using towbar-less push-back tugs for 34+ years.

Why do we even have towbars in the 21st Century?

[TCTC]

I've often wondered why aircraft don't have rear-looking cameras.

[Chiefttp]

Zurich has been using towbar-less push-back tugs for 34+ years.

Why do we even have towbars in the 21st Century?

$$$$$$$$\££££££\€€€€€€

[The Bartender]

Why do we even have towbars in the 21st Century?

Because a basic tug can be adapted to any aircraft with the use of a relatively cheap towbar, and the same tug can push a 15 ton turboprop one moment and switch over to a 200 ton widebody the next.

It's all about the cost of GSE.
Five conveyorbelts is a lot cheaper than five lower-deck loaders and a bunch of dollies. Bulkloading keeps cost down.