Tug connection

[jom1v07]

Hi all, a uni project related question for you...! In short, can a TBL tug be connected whilst a/c engines are running?

I'm working on the assumption that a conventional tug can; tow bars are obviously detached after push back so the other way should be ok too? I've got no experience with TBLs though, so would appreciate your feedback!

Thanks in advance :ok:

[jerboy]

Yeah of course they can. Engines are started up on pushback the same as with a traditional tug, or before if an airstart is needed.

Not sure about any further specifics, but hope that helps :ok:

[jom1v07]

Sorry just re-read my post and realise I didn't word it very well! By connected i mean the act of connecting rather than being connected. Ie engines on then connect tug?

[jerboy]

Oh right, I didn't read the question very well either!

I'm not sure whether its possible tbh, (I've got a feeling it probably is ok). But why would you want to?

[jom1v07]

Sport? My dissertation's a study/simulation of towing a/c to/from stand/runway... so to save a warm down time on arrival.

Thanks for your input though Jerboy.

PS From what I read I realise the idea isn't too popular on these forums! So incase anyone plans on flaming me its only undergrad unpublished bo:mad:cks! :}

[Exaviator]

jom1v07 (http://www.pprune.org/members/316164-jom1v07), the simple answer your question is, yes. Several international airports have parking bays that require the aircraft to be towed to. Heathrow cargo area is a classic example. The aircraft will taxi into the alley way and be brought to a stop. The ground engineer will then establish communication with the cockpit, the tug will be connected, and then the O.K. to shut down engines will be given. The aircraft is then towed the remaining distance to the parking bay. I trust this helps your studies :ok:

[DidIdothat]

Hi,
A TBL should not be attached to an aircraft with the engines running as the procedures require the nose wheel chocks to be removed. This should not be done on stand with engines running.

These are manufacturers procs.

Did

[SteadyEDI]

It is possible to connect a TBL tug whilst engines are running, but would only be needed in a few rare situations, such as those mentioned above at LHR Cargo. Other than that safety regulations would advise against it.

[TOWTEAMBASE]

I agree with dididothat. The TBL should never be attached whilst the engines are running. Why exactly would the engines stay live until you've connected it up?? for a start, it means putting the bypass pin in, and relying on the captain to have actualy set his brakes. The aircraft should be chocked by the mains wheels whilst the tug is connected, and then removed....none of which can be done while the engines are running for obvious reasons. ive towed aircraft in to the apron before because of the proximty of the engines to other aircraft or buildings etc, but they would ALWAYS shut down before connecting even a conventional tug. all sounds very dodgy to me.....a few SOP's need looking at and rewritting id say

[GRIZZLER]

seems like this is a bit of a grey area....i myself have been on a push back with engines running.....have disconected tug taken out bypass pin....then aircraft has had a tech problem...we have then put pin back in and reconected tug and brought plane back on stand with engines running so it could have ground power/fep and a chat with ground engineer.

also a few years ago we used to meet an electra on the taxiway with the tug and bar...it kept one engine running while we pushed it backwards onto the stand.

[TOWTEAMBASE]

if they had engines running.....y tow it......y not taxi

[Jack_P]

of course it would depend on the circumstance..


For me, I would ensure the following was confirmed

- Hand signal given to indicate parking brake set.....

-Approach aircraft and Headset operator confirm engines are set to ground idle...

-All of the above acceptable, insert bypass pin and connect pushback tractor

YouTube - speedbird7201's Channel (http://www.youtube.com/user/speedbird7201#p/u/16/J8fgRn6KDmI)


The above link is the company I work for, and as you can see the tractor is pushing with the engines running.
If say it encountered a technical fault for whatever reason, the connection while engine run shouldn't be a problem "but" the engines must be at ground idle.

If you where to talk about from Runway to stand towing, maybe think about inbuilt GPU's on-board the tractors, so once connected a GPU lead can power the aircraft resulting in the engines being shut down....

TBL's are not recommended from Runway to stand tow, as the scoop* or cradle can rip the landing lights/taxi-way lights resulting in expensive problems....


Exaviator, those stands where the aircraft are parked backwards are to ensure the tail does not hang over the RZ and taxi-way, and are usually empty in terms of load on entering the stands, unlike the normal cargo stands like 609 where the CX freighter parks, where conventional parking happens.

LCY has push onto option but usually the APU is used to compensate for Loss of power or 1 prop is left on feathered (last time i flew into City)

BAA encourage TBL's not to be used for the reasons as a above when collection stricken aircraft from the runway, however I herd once, that in Arab Emirates there was talk of an electric belt as such similar to that of an aircraft carrier which latched onto the nose gear on taxi off from the runway..... This was then automated and parked the aircraft without any power input from the aircraft
If this actually happened like the idea that Richard Branson wanted to save money and the e-zone by towing to the hold points, and starting up by the runway threshold prior to takeoff, then we may be onto a winner...

[GRIZZLER]

only doing what the Captain asked......i tend not to argue with them on pushback as i'm only the headset man.

[Jack_P]

so your saying if the pilot asks you to jump off a bridge you would do it?
Joking aside the only thing you must never do with a tractor connected is allow the captain to crossbleed and start unless you want a tug in the side f the aircraft

[TurningFinals]

require the nose wheel chocks to be removed. This should not be done on stand with engines running.

I don't think that's strictly true. Where I work we do not do pushbacks, so the aircraft starts both engines on stand with either a headset man or someone giving hand signals, the chocks are then removed and the aircraft self-maneuvers off stand with the aid of a marshaller.

[TOWTEAMBASE]

yep, thats how you depart a free standing a/c, we are talking starting up the engines and then connecting a tug !!!

JACK P

Thats not strictly true about the runway/taxiway towing. The only way you would damage a taxiway light with the cradle is whilst connecting/disconnecting, as the cradle will be raised whilst the aircraft is in motion. This is why its suggested that the final position of the nosewheel after pushback is either between the greens, or slightly aside the center line

[Jack_P]

Of course some airports do have self taxi-out stands or power back options, however the original post asked could a TBL connect to an aircraft with running engines.

The TBL requires main gear chocking in comparison to nose is due to the cradle, and the risk of chocks being wedged into the wheels, preventing the tractor from being able to move the aircrafts

[Jack_P]

The reason i mentioned the runway lighting is because BAA have called us stating they didnt want our tugs salvaging a stricken aeroplane from the runway due cradle damaging the lights... Of course its a low chance of it actually happening but we have also had the tugs cradles software throw the systems out of sync as a result of not pushing just off the line or in-between the lights.

some-times we have problems connecting the tugs during airstarts due to the Fixed ground power being in the way. Therefore some drivers wait until the engine has started, and then connect to the aircraft, which hasn't been a problem

[TOWTEAMBASE]

agreed, and i have seen an aircraft pushed with the nosewheel chocked believe it or not....they found out when the chocks were laying in the taxiway whilst being disconnected....dont ask me how it held the nosewheel but it did. But my argument would still be WHY woould you want to start up before connection. For starters you would have an unchoked a/c with its engines running, with the potential of moving under power, and secondly, the captain would want to be ready for push ie tug connected before starting engines and wasting fuel. even with an airstart, i have never heard of start up before connection

[jom1v07]

Thanks all! :ok:

[DAVYDAY]

1. AIRCRAFT SHUTS DOWN ENGINES
2. AIRCRAFT IS CHOCKED
3.ALL BEACONS ARE OFF.


TOWBAR CAN THEN BE CONNECTED OR PIN AND TBL CAN BE CONNECTED NEVER EVER CONNECT WHEN ENGINES ARE RUNNING.

1-CAPTAINS FLY THE AIRCRAFT
2- Trained RAMP CREWS CONTROL ON THE GROUND

IF A FLIGHT CREW WANT TO CONNECT WHILE ENGINES ARE RUNNING GET THEM TO DO IT THEMSELVES

IN ALL THE YEARS OF RAMP SAFETY AWARENESS AND VARIOUS FATALITIES.THIS QUESTION SHOULD NOT HAVE BEEN ASKED!:=

Get your company to write to the airline and ask them to attend IATA/
ISAGO (IATA safety Audit for Ground Operations) course,maybe also an Idea to get your company trainers on it as quickly as poss.

DD





















NEVER CONNECT A TOWBAR OR