Some interesting facts from my tour of KLM’s engine overhaul workshop

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On Monday I got a tour of KLM Engine Services at Amsterdam Schiphol.

Most of you will know that the most expensive part of a new aircraft is the engines.  What you might not know is the huge cost involved in maintaining them.

KLM, like most major airlines, runs its own engine maintenance operation.  As well as looking after various KLM and Air France fleets, it also takes in work from other airlines.

(Note: these photos are all fairly similar because I was not allowed to show any employees or any details which would identify the owner of any particular engine.)

Click on any picture to enlarge slightly:

KLM Engine Services tour

The financials are staggering.  For a long-haul aircraft, the engine requires a full overhaul every 25,000 – 30,000 hours of flying time.  This means every 5-8 years in practice.

The full overhaul will take three months to complete.  The cost will be 50% of the cost of buying a new engine, so up to $15m.  Even a standard short-haul engine will cost $3m+.

KLM Engine Services tour

Because a plane which does not fly is a plane which does not make any money, replacement engines are fitted whilst the originals are being fixed.  This can cost up to $250,000 per month in lease costs – assuming that KLM does not have a spare in stock – so there is real pressure to get the overhaul done as quickly as possible.

KLM Engine Services tour

The workshop at Schiphol can comfortably handle 50 engine overhauls at once, and runs at 200-250 completed jobs per year.  Land has already been acquired for an extension which would take capacity up to 300 engines per year.

Competition is apparently tough, however.  There are 45 similar sites across the globe, many in lower cost countries than the Netherlands.  In an attempt to create stability, GE will now only allow licensed operators to overhaul its new generation of engines and is restricting license issuing.

KLM Engine Services tour

Even now, sites like KLM Engine Systems will not work on all aircraft types.  Engineers are specifically trained by engine and specialist equipment is required for each engine type.  Expansion into a new engine class requires careful analysis of the potential supply and demand.

KLM Engine Services tour

In the past, airlines were happy with ‘parts pooling’ and would allow parts to be swapped between engines owned by ‘friendly’ airline partners because it often allowed one engine to return to service more quickly.  This is no longer the case, partly because research has shown that engines are more efficient if they retain more of their original parts and partly because many engines are now owned by leasing companies who have no interest in sharing components.

KLM Engine Services tour

Whether or not parts are shared, documentation is key.  Paper records are still kept of every single component in an engine.  There must be a paper trail showing that the part is original (there is a black market in cheap non-OEM parts, especially for ‘bread and butter’ components) and has been examined.

We were told that it was not unheard of for an entire engine to be stripped down again because the paperwork was missing for a single tiny component somewhere inside.

KLM Engine Services tour

The factory is not usually open to the public so you cannot visit yourself.  Hopefully this article has given you a bit of insight into a key part of the aviation business that is rarely considered.

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  1. OT
    Me and my wife missed a mad-nrt flight in J , that we paid in avios the other day due to delayed connection alc-mad. Iberia said that as the connecting flight was on separate ticket, tuff titty, lost it all.
    After several hours arguing the toss with them we managed to get the only pleasant member of staff to reverse the no-show status of the flight so we could get back in biz if we made our own way there on new tickets BUT she couldn’t guarantee it ????
    We bought new returns in eco.
    We now have, in theory 2 tix for the same return flight back, 1 in each class.
    I,m going to be the first person in the queue on the morning of our return, wondered if anyone experienced anything similar and what was the outcome.

    • Would your insurance not cover you for the missed flight?

      • Yes, insurance will cover the cost of the new tix in economy in principal. They would not, unsuprisingly, cover the €5.5k each that iberia wanted to fly out 2 days later in J.
        Things is we’d really like to return in J as its 13.5 hours….
        Whilst at barajas I called amex, as am plat, to see what they could do, as i paid taxes & charges with card….sadly nothing for missed flights.

    • TGLoyalty says:

      Was the connecting flight with iberia? Really surprised they didn’t put you on the next available flight in whichever class they could.

  2. Documentary about a 747 strip down and check at BA Cardiff from 2012. Available on player until 30/10/2018

  3. Anthony Dunn says:

    Having spent a decade working in MODUK and having spent a period working on RAF aircraft maintenance and logistics, I recall being told by a senior RAF engineer that a project had “reached maturity” when the weight of the paperwork equalled the all-up weight of the aircraft itself. Looks as if the same applies in civil aviation as well.

  4. Stevie M says:

    Great article Rob. Thank you

  5. You mention not being able to take any photos which could identify the owner of an engine. Does this mean that they take on work for carriers outside of the KLM family?

    • Mr(s) Entitled says:

      “KLM, like most major airlines, runs its own engine maintenance operation. As well as looking after various KLM and Air France fleets, it also takes in work from other airlines.”

      • Lady London says:

        I think Lufthansa does too. For sure they will take in other airlines’ kit. doesn’t LH have a maintenance centre somewhere like Singapore?

  6. Nigel the pensioner says:

    Our daughter flies various helicopters – as a hobby……well aware of maintenance costs!! ????

  7. We used to use Lufthansa for our engine mx as I recall, and HAECO for our A, C and D checks.

    If you think engine overhauls are painful, take a look at a commercial aircraft’s “heavy” D Check! These often have to be scheduled in YEARS in advance due to the downtime required and the fact that it isn’t as simple to swap out a “spare” fuselage as an engine!

  8. I wonder how the move to “power by the hour” leasing for engines will affect in-house facilities. Will they bid for the contract for to do the maintenance?

    • These new leasing contracts usually mean the provider arranges for overhauls. Rolls Royce has a small facility at Heathrow and a larger one at Derby for it. BA’s newer engines are all leased, which means they have no overhaul costs directly incurred (i.e. it’s all part of the contract).

  9. Aeronaut says:

    Fascinating stuff. An overhaul costing half of a new engine is quite something.

  10. Nicholas says:

    Thanks Rob – this was really interesting to read!

  11. I love seeing this stuff! Nothing wrong with a bit of aircraft geekery…

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