U/S Instruments - should an aircraft be flown with them?
 

I was interested by a comment in another thread reference aircraft instruments being u/s, and yet the aircraft still airworthy.

Forgive my ignorance but methinks that if ANY instruments are u/s in an aircraft, then the whole aircraft is u/s and not flown?! In our club this is certainly the case. The only thing we will fly with (as I do frequently) is a DI which throughout a lengthy navex requires realigning with the compass. My QFI explained that this is because the instrument is just old, but it is a fault that we know about and can live with. I would be interested to hear what the experience is of those experienced ladies and gentlemen ppruners.

Thanks all
GQ

Flying in vmc to vfr? Oil pressure and temperature, rpm, asi, altimeter, magnetic compass should do the trick. Anything else your local airworthiness authorities require and job done. A turn and slip is on the french list, but the turn part of ours has an off switch and I wouldn't worry if it failed. I do like to have a cylinder head temp gauge but can live without it if not towing.

Very shortly the EU Law will say something like this:

For a transport aeroplane there's a document called the MEL - Minimum Equipment List, which defined the stuff that has to be working.

For e.g. training aeroplanes, the document trail is a little vaguer, but ultimately a decision is made by the Captain, or if a student is flying it, the club, as to what is considered essential.

There are however numerous cases where it's perfectly reasonable and safe to fly an aeroplane, even in the training environment, with unserviceable instruments. You don't for VFR flying need many of the IFR instruments (AI, T&S...), for much flying the compass will serve without the DI being serviceable, very often the second altimeter is only a "nice to have".

Engine instruments are again subject to opinion to some extent. EGT isn't strictly required on most engines, whilst similarly unless you have a variable pitch prop, an MAP gauge is no more than a nice to have. On the other hand, I'd not fly many - if any - 4-stroke engines without a working oil pressure gauge, for example.

On the other hand, if instruments are fitted, I'd always much rather have them working than not! In a well run club, insisting on a high degree of serviceability is thoroughly sensible.

G

U/S Instruments
 

As Genghis states, unless the aircraft has a specific MEL (PT usually) then the situation rather rests with the operator (AND THEIR CLIENTS).
If the operator offers a machine that lacks some of what would be considered 'basic instuments' then i feel the client would do well to look elsewhere for a machine. If you are training how does one get used to scanning for information if no information is available. I would suggest that an economical attitude to servicability is not an ideal environment for training or aircraft hire;especially for low hours pilots.
Simple querstion; how do you justify not providing a 'fit for purpose machine' on a regular basis.

I don't know of any piston GA plane which has an MEL.

What can be relevant is anything in the airworthiness limitations section of the POH; that stuff is mandatory.

But in general for VFR you need very little in the way of nav/com avionics. You are likely to need specified engine instruments though: oil temp, oil pressure, RPM, etc.
Not a question you want to ask too casually having walked into the average flying school :)

The answer has to be that this is a competitive business in which almost nobody is making loads of money, so the name of the game is how far the fleet can be run into the ground without losing too much business. It's a bit like running an ISP :)

I walked out of one school, 20hrs into my PPL, due to crap (dangerous) maintenance.
That is certainly not the case legally, in private GA.

If I may say so, that is perhaps because you are operating very simple aircraft.

I, as a private owner with adequate funding, can and do operate a TB20 on that basis, but I have never heard of a commercial owner who does that, on aircraft with anything vaguely resembling a decent VFR/IFR capability. You might have two radios, of which each costs $4000 to replace, or perhaps $2000 on an exchange/overhaul basis. Most owners are not going to do that immediately. It is made a lot easier by having various spare avionics on the shelf, but again most owners don't have that. I bought a pile of stuff from some Americans who upgraded to a Garmin 500 or Aspen :)

I spent all day yesterday flying one... Different levels of experience, I guess, you and I.

Go on, Peter, you'll doubtless be able to tell me why some GA piston aircraft do operate under MELs, if you put your mind to it.

The crucial difference between the hypothetical private pilot finger-in-the-air and the MEL is that the MEL should consider subsequent failures and meets the authority's expectations.

Would you care to explain the paper trail which supports operation of defective GA aircraft without MELs, please?

Which one was it?

If you really wanted to teach somebody something, Mr Hamster, you would have posted the type, and the details. Instead you just want to wave your willy, by posting half the info. Next time you will be saying you are the head of training at an FTO and a CAA examiner.

I picked up one error in your post though: "authority" is spelt with an uppercase "A".

The Islander certainly does, I remember writing one version of it when I was working for B-N.


The actual process is that the manufacturer generates an MMEL, then the operator creates their own MEL as part of their AOC procedures.

However, without an AOC, there's no legal requirement for an MEL, and it can be far more trouble than it's worth if there's no legal requirement for it.


A badly written MEL can be an utter menace - I had much mucking about recently with an aeroplane where some pillock a few years back managed to write the satcom system into the MEL, so we had to go through all sorts of stupid paperwork hoops to legally fly when one of the satcom LRUs fell over.

G

I think the CAA adopt the FAA generic single engine MMEL for most types - for example the A1 Single Engine one for PA28.

PA 28 FAA MMEL: Single Engine Aeroplanes Revision 1 | Publications | CAA

So is there somewhere a list of items which are required for a particular non-air transport flight? Is it up to the pilot what is required for the intended flight?

I was regularly flying in a permit aircraft with U/S nav equipment. Eventually the operator removed all of the nav equipment from the plane (must have been properly unserviceable!). I'm told that a new W&B had to be done after all the extra aerials and wiring were removed and there is now a slightly higher cruise and better fuel economy...

Peter, in a moment of unexpected and ill-judged childishness, you wrote:

I was referring to the competent authority, not a particular Authority.

This might help:

List of Master Minimum Equipment Lists | Publications | CAA

The type I was flying is on the list, though it was not a G-registered aircraft.

I'm neither Head of Training nor a CAA (or DGAC) examiner... Much higher up the food chain than both of those! :)

The TADS or HADS for BMAA administered microlights have a de-facto MEL, which varies between types.

LAA paperwork is a bit more random.


There are requirements in the ANO of-course for minimum instrument fits for certain types of airspace.

G

Hi GQ,
Something I'm surprised nobody has picked up on is your comment about the DG needing realignment occasionally.
This is caused by precession due to the rotation of the earth. Admittedly a worn instrument makes it worse.
You will learn about it when you get to the technicals then you can inform your engineer.:ok:
D.O.

You're most kind... ;)

(I've never been to a bad party at an embassy, but have never never been the host either...).

Still waiting for Peter to return and answer my question...

Since the OP asks about a club environment, let's just go back to the new EU Ops regs that whopity quoted, since they apply to a renter.

It says that you need to fly in accordance with an MEL if you want to operate with less than the REQUIRED instruments.



So - which ones are required ones?

• Whatever is required in the POH, of course (Typically section 2 - Limitations, but might be elsewhere or in several places)
• For VFR, a magnetic compass, a clock, an altimeter, and an airspeed indicator (NCO.IDE.A.120)
• For IFR, in addition turn-and-slip, attitude, vertical speed, DI, outside temperature (NCO.IDE.A.125)
• For VFR night as under IFR, but you don't need the thermometer (NCO.IDE.A.120)
• At night, various lights (NCO.IDE.A.115)
• A first aid kit (NCO.IDE.A.145) and a fire extingisher (NCO.IDE.A.160)
• Radios, nav receivers etc. if they are required by the airspace you want to fly in or to maintain the route (various)

So, in your case, very little indeed. But this is for private ops, ie, you as a renter. If you are receiving training, the operations manual of the training organisation is relevant, and it might well have a MEL or other rules you should stick to.
As an aside - in the new EU OPS world, which part does actually apply to training organisations during training?

See above - for non-comercial non-complex ops there is no requirement for an MEL, and you can operate in accordance with the legal minimum requirements and the requirements in the POH (an obey both). Indeed since MELs need approval by "the authority", the "authority" would be hard pressed if they jad to agree MELs with every single spamcan owner...

I'll play along...

To begin:

Where is your reference that only AFM Section 2 contains the restrictions?

I'm not surprised. You're posts on this thread are reeking of smugness, and I certainly wouldn't take your bait if I was h im.

Why don't you just help us and generously pass on your knowledge in a kind open and honest mannor as most knowledegable posters here do? I'm sure we all enjoy learning something new when the knowledge is imparted in a friendly way.

If you are trying to show us how much more intelligent you are than the rest of us, then I'm afraid that I'm getting a very different impression from your posts; one that I'm sure you wouldn't like to be convayed.

No.

Lots of people are confidently proclaiming that this, that, or the other, is hard fact. Very little of it is. The best answer is to challenge falsehoods.

Too much time is wasted by people reading and posting in forums such as this rather than finding out the right answers, or indeed, valid questions. I get fed up of this because it's damaging the pilot community in general.

I'm happy to pay along with funny games such as cjboy's, but am very well aware of my own frailties. That awareness has served me well for many years in many cockpits and flight decks, not to mention board rooms, courts, and other pressurised situations.

Peterh, in particular, is a purveyor of mis-information hidden behind an aura of experience and expertise, in my opinion.

If you want knowledge, go to the original sources; don't waste your effort in an internet chat-room.