MEL

[BobtheBuilder707]

Hi all, Apologies if this has been asked before (I am trying to brush up on my knowledge before starting my line training on the S92), but I have difficulty understanding the quote "May be inop as long as the aircraft has not made more than one flight"

Is my understanding correct that If the aircraft gets an unserviceability inflight, and according to the MEL the aircraft may continue the flight as long as the aircraft has not made more than 1 flight!! -Does this mean that if we land offshore we're stuck, or does it mean that because the unserviceability occurred inflight, the aircraft can take off again and return back to the departure airfield?

Thank you,

BtB

[Greeny9]

one more flight post the fault/defect I would presume.

[tu154]

It's a 'gotcha' and will depend on what the definition of 'one flight' is in the MEL, it will be defined somewhere. In many cases once you land the aircraft can't take off again. In the UK there is then an approval process to go through to have the aircraft ferried back to base without pax to have the defect rectified.

[BobtheBuilder707]

Hi,

MEL of our operator states: a flight is a period of time between the moment when an aircraft begins to move by its own means, for the purpose of preparing for t/o, until the moment the a/c comes to a complete stop on its parking area after the subsequent landing (and no subsequent take off).

Cheers,

BtB

[bb in ca]

I'm not sure if this addresses your question or not but generally speaking when...

Airborne - reference the emergency checklist *

On ground - reference the MEL

* It is often prudent to reference the MEL once you are aware of a defect as it may dictate where you choose to land.

Beware of pilot and mechanics who MEL everything under the sun without doing due diligence to investigate the reason for the failure. That small defect may be the tip of the iceberg that's about to ruin your day.

Fly safe!

[rick1128]

Unfortunately, I an see way too many pilots out in the aviation industry as a whole that do not have a good handle on how to properly utilize an MEL. Some of the problems have to do with what happens or should happen after an item is MEL'ed.

Just because an item is MEL'ed, doesn't mean that you have to or should operate the aircraft. A lot goes into that decision. What is the problem? What is the experience level of the pilot? What is the weather conditions? What is the flight mission? Say the rotor brake is MEL'ed. Is it flyable? Yes. Do you really want to take it off shore to a rig when the winds at 30Kts with gusts to 45 knots? Probably not.

Next, how does the MEL'ed item effect possible emergency situations and procedures?

With the more and more advanced avionics making their way into the newer helicopters, what effect would an MEL'ed item have on other systems. For example the FMS could be tied into the Ground Proximity Warning systems and the TCAS.

When you operate under an MEL, some thought has to go into utilizing it properly and more important safely.

[BobtheBuilder707]

So, if a fault occurs once in the cruise!!!, and the MEL states that it may be inop provided the aircraft has not made more than 1 flights since the item was last serviceable (a flight= period of time between the moment when a/c begins to move by its own means, for purpose of preparing for t/o, until the moment the a/c comes to a complete stop on its parking spot after the subsequent landing, and no subsequent t/o's)! ...so, I read this as, if you land offshore in this scenario u'r stuffed!!??

BtB

[tu154]

So in that case, assuming you became aware of it in flight and could go through a decision making process, you could elect to RTB and not get stuffed?

[steve_oc]

First thing, my interpretation in this case would be that having "discovered" the fault in the flight on the way offshore, you would then be permitted to make one further flight back to your maintenance base. That complies with the alleviation that you can not make more than one further flight.
Second thing, as mentioned above, you would be wise to consider turning round and going home when you discover the fault, to save any ensuing hassle. Your emergency procedures may point you in this direction anyway.

[BobtheBuilder707]

That makes sense! Although a fellow pilot told me that the MEL only applies when on the ground, so if a fault occurs inflight (same scenario) and ur only aloud one flight since the item became unserviceable you can land offshore and still t/o to return to departure airfield???

Does that makes sense, as I thought that it wouldn't matter if the fault occurred on the ground or after t/o as its part of the same 'flight' ??? ,so RTB or get stuck.

BtB

[BobtheBuilder707]

Steve,

Does it matter if you discover the fault inflight or before t/o (with the MEL criteria of only being aloud 1 flight since the item became u/s) with regards to getting stuck offshore or being able to lift again to return home to the maintenance base?

BtB

[steve_oc]

Yes the MEL only applies on the ground (or helideck), if something happens in flight you have an emergency checklist written for that very purpose (hopefully). If you therefore land (anywhere) with the fault, you then have to refer to the MEL to see if you can take off again. Depending on the fault, the MEL may say the item "may be inoperative for VFR" or, as in this case, "may be inoperative provided only one flight has been made since the fault was discovered". This means (normally after discussion with your ops and engineering people) you can take off again; the flight during which the fault occurred does not count as the "one flight since the fault was discovered". Of course you may decide, or your checklist may tell you, to "land as soon as practical" when you discover the fault, in which case you would turn round and fly back to base, at which point it becomes Engineering's problem. Does that all make sense?

[BobtheBuilder707]

Many thanks for the detailed explanation Steve. yes, that all makes sense now!

BtB