Are there significant differences for you Mechanics between aircraft types? Are some more difficult than others? Please let us know the challenges in your job.



Thanks.

Question For the Mechanics: Which Commercial Aircraft Have Been Easiest and Most Difficult For You to Work On?

Apart from the pilots.

I think every aircraft has its challenges.

On the JT9 equipped Classic Jumbos, the PRBC and the Fuel/Air converter were a pain.

Just about anything you do on the tail engine of the DC10/MD11 can be a challenge.

It seems that the PTU on the B757 was hung from the assembly building ceiling and the aircraft built around it.

My point is, every aircraft has its good points and its bad points. Each manufacturer approaches certain challenges their own way.

I think, if it’s thought about, mechanics will like working on the aircraft they are most comfortable with.

Starlionblue wrote:

Apart from the pilots.

The yoke actuator and the short between the headset are a problem that transcends aircraft type.

PRBC?

fr8mech wrote:

Starlionblue wrote:

Apart from the pilots.

The yoke actuator and the short between the headset are a problem that transcends aircraft type.

Starlionblue wrote:

PRBC?

Pressure Ratio Bleed Control?

fr8mech wrote:

The yoke actuator and the short between the headset are a problem that transcends aircraft type.

You win the internet for the day....

fr8mech wrote:

I think every aircraft has its challenges.

On the JT9 equipped Classic Jumbos, the PRBC and the Fuel/Air converter were a pain.

Just about anything you do on the tail engine of the DC10/MD11 can no be a challenge.

It seems that the PTU on the B757 was hung from the assembly building ceiling and the aircraft built around it.

My point is, every aircraft has its good points and its bad points. Each manufacturer approaches certain challenges their own way.

I think, if it’s thought about, mechanics will like working on the aircraft they are most comfortable with.

Starlionblue wrote:

Apart from the pilots.

The yoke actuator and the short between the headset are a problem that transcends aircraft type.

Thanks for your post and the last line was a killer.

889091 wrote:

Pressure Ratio Bleed Control?

Yes. Sorry, that’s some old school stuff there. Pratt buried that thing in the engine at about the 1130 position, in about the most inaccessible place.

As I recall, TWA modified their engines to move all the bleed components, except the valves, to the 7oclock position. Much more accessible, but more lines=more potential leaks.

This question is more easily answered with regards to engines. For me, no question, the easiest engine is the RR Trent 892. Most things are mounted on the fan case, which gives much easier access. Fuel control changes are a breeze. It’s not always RR. PW2000s had the edge over the RR211. Late model CF6’s were the absolute worst. JT8s not to bad as long you have a suitable platform.

Lpbri wrote:

This question is more easily answered with regards to engines. For me, no question, the easiest engine is the RR Trent 892. Most things are mounted on the fan case, which gives much easier access. Fuel control changes are a breeze. It’s not always RR. PW2000s had the edge over the RR211. Late model CF6’s were the absolute worst. JT8s not to bad as long you have a suitable platform.

Are you referencing the RR211-535's on 757's versus the PW2000 on the 757? I've heard different things about each engine. DL swore by the PW, yet I believe the majority of carriers ultimately opted for the 535. It sounds like you feel from a mechanics point of view the PW engine was easier to maintain and work on.

Old timers I talked to were always split between whether the DC8 or 707 were more irritating to work on. It always sounded like neither were a walk in the park.

Like what was said before, all airplanes have the good and the bad. I enjoyed the E145, the ATR, A300 and 757/767. Don't have very many good memories from working on the CRJ200 but the 700/900 was better. Didn't like the E120. The MD10/11 are a mixed bag. The 10's aren't bad except for the #2 engine, but the 11's seem to have more small issues. A lot of that also comes from what your used to working on. Another big factor is the company you work for. If you take care of the equipment, you tend to enjoy you job more than always having to fix 10 things to get the 1 write up fixed.

In my career in aircraft maintenance, I've always worked structures and composites. For me, the Lockheed L1011 had one of the best structural repair manuals. It was simple, straight-forward, and gave you clear and concise graphics and information. The aircraft itself was easy to work on as it was a wide-body with big compartments.
I prefer to do structural repairs on the Boeing aircraft versus Airbus. Yes, there may be some bias in play here, but to me Boeing's structural repair manuals are easier to understand versus the Airbus structures manuals. But, this may be only to the fact that I've been trained on the Boeing manuals and here at IND (FedEx heavy maintenance) we don't usually work on the Airbus fleet unless it's a flight line call.This is not to say that Airbus doesn't make a quality product, they do. It just seems to me that Airbus repairs, from a structural point of view, seem to be somewhat "complicated" as if you were doing the structural repair in the factory instead of out on a flight line.
As for the Boeing's, we work on the B757, B767, and MD11's. Also the MD10-30's. The -30's are supposedly going away soon like the MD10-10's. The MD's were a good ship to work on except for the # 2 engine area. First of all, the number two engine is way up there from the ground. You had to find some way to get up there, and then it was a lot of going "up and down" to get tools and supplies, stringing air hoses and such to get the job done. Because of this, I would say that we in aircraft maintenance prefer the wing-mounted aircraft such as the B757, B767, and others. It just makes our jobs that much easier to do.
Thank you for your inquiry into aircraft maintenance.

Gregory

Probably the biggest headache for me is the MD-11. Never mind the spare engine in the tail.

The eleven is a text book example of what happens when a manufacturer decides to cheap out. The plane is beset with all sorts of wiring issues. Why, because MD decided to use Kapton wiring when they built the thing. Even though by the time the -11 came to fruition the industry knew Kapton was junk. And now we get to deal with all the intermittent faults , shorts to ground, broken wires etc.

It has more than it's fair share of what the hell were they thinking moments. My all time favorite is the ant-skid shutoff valve design, of which it has two. One in each wheel well. Who ever was responsible for that system never heard of drip loops. That's because instead of having the electrical connector on the side with wiring going to it having a loop the connector is on the top of the valve. Which provides a nice pathway for fluid, usually skydrol, to get into the valve connector. That's when you start getting intermittent auto brake faults. Which requires not only replacement of the valve but the shipside connector as well.

The list goes on. However, with that said the MD-11 keeps me employed, lol.

Lpbri wrote:

This question is more easily answered with regards to engines. For me, no question, the easiest engine is the RR Trent 892. Most things are mounted on the fan case, which gives much easier access. Fuel control changes are a breeze. It’s not always RR. PW2000s had the edge over the RR211. Late model CF6’s were the absolute worst. JT8s not to bad as long you have a suitable platform.

I've changed the BUG on a Trent 892 powered 777 and one on a GE90 powered 777. The RR by far was much easier, and quicker.

ElroyJetson wrote:

Lpbri wrote:

This question is more easily answered with regards to engines. For me, no question, the easiest engine is the RR Trent 892. Most things are mounted on the fan case, which gives much easier access. Fuel control changes are a breeze. It’s not always RR. PW2000s had the edge over the RR211. Late model CF6’s were the absolute worst. JT8s not to bad as long you have a suitable platform.

Are you referencing the RR211-535's on 757's versus the PW2000 on the 757? I've heard different things about each engine. DL swore by the PW, yet I believe the majority of carriers ultimately opted for the 535. It sounds like you feel from a mechanics point of view the PW engine was easier to maintain and work on.

Pratts have a reputation for day to day maintenance costs and very slight fuel burn advantage. The RB211 had a longer overhaul interval that created an overall advantage in cost of opperation.

Lightsaber

lightsaber wrote:

Are you referencing the RR211-535's on 757's versus the PW2000 on the 757? I've heard different things about each engine. DL swore by the PW, yet I believe the majority of carriers ultimately opted for the 535. It sounds like you feel from a mechanics point of view the PW engine was easier to maintain and work on.

Pratts have a reputation for day to day maintenance costs and very slight fuel burn advantage. The RB211 had a longer overhaul interval that created an overall advantage in cost of opperation.

Lightsaber[/quote]

The one advantage, maintenance wise, PW200 powered 757's have over the RB211 is the location of the PRSOV. On the PW2000 it's above the hot section. For the RB211 it's in the pylon and a royal pain to remove and replace. I think when they built the pylons they put the PRSOV in a production jig and built the pylon around it.

Most difficult......hands down.... The DC-8
The overall engineering design of the aircraft was just bad.
The DC-10/MD-10/MD-11/KC-10 and the DC-9 closely follow the -8

The easiest has to be the 777. Completely mechanic friendly, you just need a ladder for EVERYTHING.

Strebav8or wrote:

Most difficult......hands down.... The DC-8
The overall engineering design of the aircraft was just bad.
The DC-10/MD-10/MD-11/KC-10 and the DC-9 closely follow the -8

The easiest has to be the 777. Completely mechanic friendly, you just need a ladder for EVERYTHING.

Rarely work on Airbus so can't really comment (despite just helped out working on a A330)

Avionics mechanic so will comment from this point of view.

737 - tight spaces everywhere but with one stepladder you can pretty much access everywhere on the aircraft. Still wonder why the thigh impact device (aka stab trim control) still exists on the NG.
747 - sorry guys I just hate it - two extra engines, two extra landing gears and an extra deck means a lot of work. Wire wrap (WHY?) and fuel tank compartments are complicated. Imagine how much fun I had when doing fuel tank wiring inspection (SFAR88) and changing out all tank units...
757 - hybrid 737/767, still can't navigate the E&E compartment without snapping my spine.
767 - loads of weird access, and with so many being produced the subtle difference between aircraft just means IPC reference is a must. Having work on them for years I am too used to it...
777 - Just great. Easy access and when things go wrong you get maintenance message.
787 - Having the UMD with you is a must. And when things go wrong it goes horribly wrong. Need nerve of steel for software updates, and hope nothing goes wrong when performing block point updates....

Engines

Still prefers GE over the other two... maybe just me got used to the layout.
Pratt (4000 series) has a tendency to destroy itself...
RR - haven't work on them much, but the RB211 on 747 nearly killed me when getting in, got horrible rash when accidentally rubbed my arm on the 700 exhaust nozzle, and surprised by the speed of spool up on the 1000

gregorygoodwin wrote:

I prefer to do structural repairs on the Boeing aircraft versus Airbus. Yes, there may be some bias in play here, but to me Boeing's structural repair manuals are easier to understand versus the Airbus structures manuals.

Every day, and twice on Sundays. The Boeing SRM is top over MDD(three volumes for the SRM???) and Airbus is a pain.

Structures, bonded structures and composites(there is a difference) is most of my work, with odd time spend with the grease monkeys when things were slow.

On the A330 powerplants:
PW parts are expensive, the part numbering is illogical, the manuals aren't that bad.
GE, easy manuals, parts are much less, and readily available.
RR, an abomination, but great on wing time, manuals are rubbish, parts are astronomical. $11M for a shop visit? Ouch.

Strebav8or wrote:

Most difficult......hands down.... The DC-8
The overall engineering design of the aircraft was just bad.
The DC-10/MD-10/MD-11/KC-10 and the DC-9 closely follow the -8

The easiest has to be the 777. Completely mechanic friendly, you just need a ladder for EVERYTHING.

Depends.

Lubrication for example.
On the MD-11 it's almost exclusively grease 28 (talking about flight controls and landing gear). Only a hand full of grease points on the horizontal stabilizer need a different grease. Quick access panels on the leading edges of the wings make slat lubrication easy. Only a hand full of grease points on the flaps.
On the 777 it's almost exclusively grease 33, which can stink horribly depending on the supplier. The landing gear alone needs like 4 or so different types of grease. There's a ton of grease points on each flap track. You need to open almost all leading edge panels for slat drive lubrication/service.

Gear change / oleo seal change.
Clear winner is the MD-11. Smaller, straight main landing gear with two trunnion pins. No spherical bearing. The 777 landing gear is just huge and not as easy to handle. The angle makes a seal change definitely harder than on the MD-11.

Engine change (GE engines).
The GE90 has fewer parts to disconnect. The CF6 is easier to lower and raise, as it hangs almost straight under the wing, not with that annoying 7° tilt. On the MD-11 the forward mount bolts are harder to tighten than the aft mount bolts, on the 777 it's the opposite. Easy access on the fwd mount, pain in the butt on the aft mount.

Tank work.
The MD-11 doesn't have NGS, so preparation and the actual work is less complicated. There are many access panels on the upper surface of the wing, which makes it easier to access these compartments. The fuel system of the MD-11 is much more complex though, so there's more stuff to go bust and therefore more tank work in general. And the lower aux tank and tail tank are a HUGE pain in the butt.
And here I can throw in a third aircraft, the A330. Navigating in the tanks can be quite difficult due to the layout. And the internal access panels suck.

APU.
The 777 APU is very reliably. I personally have never had to uplift oil in 8 years of working with the 777.
The MD-11 APU is just crap. It's unreliable, has a short life time and there just isn't any space left in the APU compartment as it had to be moved forward under the horizontal stabilizer.

Circuit breakers:
Almost all circuit breakers on the MD-11 are located on the flight deck. A few related to water/waste, doors and other cabin stuff are located in the cabin ceiling behind the fwd entry doors, each cargo compartment has a few CBs dedicated to the cargo loading system, and there are just a hand full in the center accessory compartment, mostly APU starting and miscellaneous.
The 777 has the overhead CB panel on the flight deck, there are 7 CB panels in the main equipment center, each of the 4 flight control power supply assemblies has a set of circuit breakers (one of the four is located in the fwd lower cargo door frame), there are additional circuit breakers in each lower cargo door frame for the cargo handling system, some more CBs in the aft cabin ceiling or behind the sidewall of the bulk cargo compartment for the APU for example, and of course the CBs for the cargo loading system on the main deck are distributed all over the cargo compartment.

Access panels.
On the MD-11 the gaps around all access panels (except quick access panels) need to be sealed for aerodynamic smoothness. Not so on the 777. But the 777 apparently has at least one screw that is different to all the others in each access panel. Either a different head, diameter or length or a combination of those. Very annoying.

The ground service bus of the 777F is just a glorified light switch. I would expect the lavatory to be working and the potable water system and the galley air chiller, when the ground service bus is powered. But no, only the lights in the galley/supernumerary area come on.

The potable water system of the 777F overflows into the sidewall/below the floor of the lower fwd cargo compartment when it was serviced to 100% full and main AC power is switched off.

There's no OFF switch for the weather radar on the 777, so it's way to easy to accidentally irradiate someone.

Flight control cables on the MD-11 suck a lot. The tail engine sucks. Fuel shroud system sucks.


There's a lot to hate about each and every aircraft and some engineers need a slap in the face for the crap the have designed. Aircraft are (mostly) not built to be maintained/repaired, but to be flown. Which is understandable of course. But sometimes this can be actually dangerous or annoying at least.

For example once I wanted to install the spoiler locks on the 777. It worked fine for all spoilers except the innermost ones. All spoiler panels were deployed, the handle was in the deployed position and hydraulic was switched off. I couldn't fit the collar around the PCU rod because the spoiler panel has sagged a bit. 2 or 3 millimeters were missing. So I asked the coworker to switch on hydraulics to raise the spoiler panel back up. I moved clear of the spoiler panel and when the electrical pumps were switched on I waited for a few seconds, because I didn't trust this aircraft. And for a good reason. Just as I started to move towards the PCU to install the collar, the spoiler panel slammed down. What I didn't know was that by now the aircraft was set into air mode. And with aircraft "flying" and all engines off and no air speed indication, the aircraft says "No! You're not allowed to deploy the speed brakes.". There was no way to get the spoilers back up, before the aircraft was back on ground. I've learned a lesson and spoiler lubrication was deferred to another shift.

And this is the reason why I like the MD-11 more than the 777. Even though the MD is more work and has a lot of crap. It's an honest aircraft. It doesn't try to f*ck you each time you turn your back. You can follow through the whole system from the flight deck to the flight controls/engines/hydraulics/etc and back. And if there's a black box you open the manual and can follow exactly what's happening inside. With the 777 a black box (or sometimes not even a black box, but just a PCB in a rack) actually is a black box. It's all done with software and after the next update things might work differently. With the older aircraft you can do troubleshooting "off-road" of the FIM by knowing and understanding the systems.
Newer aircraft are too smart. They do things that are not taught in the trainings and are not written down in the manuals. A prominent example is MCAS on the 737MAX. But there are lesser known examples everywhere.

Horstroad wrote:

And if there's a black box you open the manual and can follow exactly what's happening inside.

The LAMM is a sweet manual. About the only thing good about the aircraft.

Every wonder why the LAMM is needed? Because the AMM, the FIM and the WDM are just about useless for telling you what’s happening.

I’ve seen better D&O’s in Haynes Manuals.

Horstroad wrote:

The 777 has the overhead CB panel on the flight deck, there are 7 CB panels in the main equipment center, each of the 4 flight control power supply assemblies has a set of circuit breakers (one of the four is located in the fwd lower cargo door frame), there are additional circuit breakers in each lower cargo door frame for the cargo handling system, some more CBs in the aft cabin ceiling or behind the sidewall of the bulk cargo compartment for the APU for example, and of course the CBs for the cargo loading system on the main deck are distributed all over the cargo compartment.

Don't forget to pull the fire bottle CBs if a 777 is left unpowered overnight...

Horstroad wrote:

There's a lot to hate about each and every aircraft and some engineers need a slap in the face for the crap the have designed. Aircraft are (mostly) not built to be maintained/repaired, but to be flown. Which is understandable of course. But sometimes this can be actually dangerous or annoying at least.

Can't agree more.

Was chatting with a network security guy few months back about the software problems on the 787 and 737Max. Yes there are plenty to improve but we concluded as long as it flies safely, and more work we do on ground is acceptable.

Dear all,

This is a highly interesting read even though I am not an aviation professional. One side question arises:
What happens if you are doing maintenance on a big jet and you happen to get "stuck" - like a system not behaving as expected, or a maintenance manual that gives unclear instructions? Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help?

Kind regards,
Hendric

hitower3 wrote:

Dear all,
Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help?

Kind regards,
Hendric

"Your call is very important to us. You are number 68 in the queue." (Insert endless loop of the same eight bars of synthetic guitar for 15 seconds. Then...) "Yor call is..."

hitower3 wrote:

Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help

CTRL+ALT+DEL fixes the Airbus.

I haven't worked for an operator, but as a maintenance organization, we submit the request via the Boeing Portal, depending on the severity/priority, is how long it will take to get a response. Boeing also had Field Service Reps.

hitower3 wrote:

Dear all,

This is a highly interesting read even though I am not an aviation professional. One side question arises:
What happens if you are doing maintenance on a big jet and you happen to get "stuck" - like a system not behaving as expected, or a maintenance manual that gives unclear instructions? Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help?

Kind regards,
Hendric

Well, at my operator, the problem gets kicked to my department. Airlines have a technical support department that develops plans to work a repetitive problem. We do have the ability to liaise with the manufacturers and even other operators if the problem is beyond our collective abilities.

But, yes, the manufactures do have a field support department. They are anything but quick. The fastest turn-around they provide normally starts at 4 hours.

celestar345 wrote:

Don't forget to pull the fire bottle CBs if a 777 is left unpowered overnight...

Yeah another great feature

fr8mech wrote:

hitower3 wrote:

What happens if you are doing maintenance on a big jet and you happen to get "stuck" - like a system not behaving as expected, or a maintenance manual that gives unclear instructions? Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help?

Well, at my operator, the problem gets kicked to my department. Airlines have a technical support department that develops plans to work a repetitive problem. We do have the ability to liaise with the manufacturers and even other operators if the problem is beyond our collective abilities.

It's the same at my operator.

The Aircraft Maintenance Manual introduction basically says:
1. Use this instruction manual.
2. If something is not in here, use standard industry practices. You're a trained professional.
3. If this doesn't help either, call us.

But it's very rare to call the manufacturer over (unexpected) system behavior. Mostly it's about structural damage well beyond the limits.

fr8mech wrote:

Airlines have a technical support department that develops plans to work a repetitive problem.

I guess I should add that, broadly, there are two types of repetitive items…those that affect one aircraft and those that affect the aircraft type or sub-fleet of that type.

The first can usually be dealt with by using sound troubleshooting practices and procedures. It may take time and a couple of iterations, especially on intermittent problems, but it’ll get fixed. Rarely is the manufacturer involved in this.

The second may be a design issue, a procedures issue, a component issue or a combination of the three. Airlines will usually have a department that manages the fleet from a reliability perspective. The solution to this type of problem may involve the manufacturer, other industry users, component vendors, regulatory agencies, etc.

LMP737 wrote:

I've changed the BUG on a Trent 892 powered 777 and one on a GE90 powered 777. The RR by far was much easier, and quicker.

I hear you! Just changing the BUG oil and filter on a GE90 is challenging enough, having to remove pipework and then trying to lockwire the drain plug. It certainly seems to be a GE thing to bury everything under layers of pipe and duct work.

LMP737 wrote:

I think when they built the pylons they put the PRSOV in a production jig and built the pylon around it.

LOL, like pretty much any component inside a pylon! I recently spend a wonderful day getting a pair of engine fire extinguisher bottles in and out of an A330 pylon. The access holes are barely big enough but fair enough I suppose, as you'd be loath to have any holes in such a critical and highly stressed component.

Strebav8or wrote:

The easiest has to be the 777. Completely mechanic friendly, you just need a ladder for EVERYTHING.

Apparently the 777 chief engineer was an ex mechanic, hence the relative ease of working on them. Some of the lube points are difficult to get to but no doubt much better than many other types.

celestar345 wrote:

the RB211 on 747 nearly killed me when getting in

You were lying across the TR and it came back on you?

Horstroad wrote:

On the 777 it's almost exclusively grease 33, which can stink horribly depending on the supplier. The landing gear alone needs like 4 or so different types of grease. There's a ton of grease points on each flap track. You need to open almost all leading edge panels for slat drive lubrication/service.

The slat panels are not too bad unless you have to drill screws out. We temporarily put the panels back with 6 screws only to make the next lube easier. This is with aircraft doing long term storage mind you.

Horstroad wrote:

But the 777 apparently has at least one screw that is different to all the others in each access panel. Either a different head, diameter or length or a combination of those. Very annoying.

Yes! Why do they do this? I've been told it's a safety thing, in that you'll put at least a few screws back in the correct location, but this does not seem logical to me.

Regards, JetMech

I have never worked on anything smaller then a 737-200/DC-9. But in My Humble Opinion the MD-90 was the worst!! From Tire changes to Eng Changes it was just a hassle. Only airplane i had to get down to my undershirt to change a cockpit window controller, and a valve behind the P-Dome.
Its a toss up between the L-1011 and the 727 as my favorite. The 777 never really broke on me except a eng change so can't really gauge it. Not a fan so far on the 220, 350 and 330neo.

hitower3 wrote:

Dear all,

This is a highly interesting read even though I am not an aviation professional. One side question arises:
What happens if you are doing maintenance on a big jet and you happen to get "stuck" - like a system not behaving as expected, or a maintenance manual that gives unclear instructions? Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help?

Kind regards,
Hendric

Working at MRO here, we would contact Boeing/Airbus Tech support for help.

extender wrote:

I haven't worked for an operator, but as a maintenance organization, we submit the request via the Boeing Portal, depending on the severity/priority, is how long it will take to get a response. Boeing also had Field Service Reps.

The quicker the response the more rubbish it gets.... Had many occasions where Boeing gave me answers that is completely wrong or useless. Let alone the NTO responses...

Although got to say, after working on the fleet for a while we have pretty good idea what can go wrong and what to do when it happens, also a lot of modificatons were installed by us (with STC) has made some of our guys expert in that system.

[quote="celestar345"]
You were lying across the TR and it came back on you?

Sliding down the exhaust for the first time to remove panel for changing the ignitor plug... and forgot to keep my head down...

On a side note... anyone here works on 787?

DISCLAIMER: I never worked on the aircraft beyond fueling it decades ago, I'm not an A&P, and am not personally qualified to speak to this... However, user twincommander commented on working on Learjets years ago. It's too good not to repost in this forum:

twincommander wrote:

If you weren't an alcoholic before you touched a Learjet, you became one after the first day of a Phase inspection.

Here are some things I remember hating (in somewhat order, least hated to worst hated) from my corporate/lifeguard days:

0.5 Recovering from the hangover due to working on a Learjet.
1. Line service misfuel the tip tanks, causing an imbalance, and having to roll a jack out to level the wing and let the fuel self level.
2. Line service properly fueling the plane, but then the flight getting cancelled and the pilots leaving the interconnect switch open after power down, causing one wing to be 3 - 4 inches off the ground, getting called in to put a jack under the wing and self level.
3. Closing the main door for a maintenance run, sometimes you won't get that stupid electric lock to work right
4. Opening the main door after said maintenance run, because you end up skinning a knuckle getting the lower half open.
5. Opening the engine cowls (731 series) for pretty much anything
6. Pulling the main ship batteries, because pilots played too long with no GPU
7. Pulling the main ship batteries, because of any other reason
8. Opening that stupid raisbeck door, and finding the only razor sharp trim edge by the inner compartment latch.
9. Hydraulic filter changes ( at least its red fluid)
10. Removing the elevator counterbalance assembly
11. Changing cables
12. Changing cables in the aft compartment
13. Changing cables in the cockpit
14. Opening any floor board
15. Removing the main gear
16. Setting the zero-null on the nose steering
17. Finding out that the shop who sent you an overhauled nose gear with steering potentiometer installed it incorrectly, and you can'tt find null.

And lastly, but I could probably add more

18. Being told you are being assigned to a Phase A - D on a company med-evac Lear 35, ergo negating any positive effects the alcohol had in numbing the pain and misery of working on the previous Lear 31 Induction inspection.

hitower3 wrote:

Dear all,

This is a highly interesting read even though I am not an aviation professional. One side question arises:
What happens if you are doing maintenance on a big jet and you happen to get "stuck" - like a system not behaving as expected, or a maintenance manual that gives unclear instructions? Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help?

Kind regards,
Hendric

Not a mechanic, but awhile back I got to watch an engine swap on a 772. (Mostly I had to babysit the actual engineers and mechanics to m make sure they didn’t go beyond what their temporary badges gave them access to and that the food was delivered on time) But I took an interest in the process, and they were kind enough to indulge my curiosity and let me in closer as long as I didn’t touch anything

It was an incredibly efficient operation. They had a giant manual/checklist that was quite literally like an IKEA instruction manual on how to remove and replace a ge90. And when they got stuck, they’d either go over and compare to the other engine that wasn’t being replaced, or call their base and talk it through with them.

It was a little jarring coming in for my babysitting shift and seeing all of them crowded around the non-broken engine with the guidebooks looking confused. We thought they’d accidentally broken that one too.

Very interesting thread though. The mechanics are usually some of my favorite people on the ramp. Buy an old mechanic a beer and you’ll hear stories about every aircraft

celestar345 wrote:

Sliding down the exhaust for the first time to remove panel for changing the ignitor plug... and forgot to keep my head down...

You hit your head on the cookie cutter?

Regards, JetMech

jetmech wrote:

celestar345 wrote:

Sliding down the exhaust for the first time to remove panel for changing the ignitor plug... and forgot to keep my head down...

You hit your head on the cookie cutter?

Regards, JetMech

Almost, only an inch away from being sliced.

Sitting on the 787 stabiliser when doing travel test was another fun thing to do...

I like to work on A330 with Trents but PW are not bad too.

Than A320 is ok, almost same technology, just engines are not that good, CFM are ok to work on them but sometimes You need to replenish 4-6 cans of oil each Daily check. And V2500 do not eat oil at all but as my practical instructor from Lufthansa Technical Training told me some 17 years ago: shit starts with opening the cowlings....
Than 737NG not bad on line mtce, but heavy checks are challenge sometimes, last spring we had to change stab trim cables it means few days spent squezed bellow cockpit floor and aft compartment.
B737 CL worse than NG, but it was first airliner I worked on and I learned a lot...
ATR nothing good about, landing gear is too low, engines too high, to change NLG wheel You need specific tool. And Troubeshooting manuals are just not useable at all.

milhaus wrote:

ATR nothing good about, landing gear is too low, engines too high, to change NLG wheel You need specific tool. And Troubeshooting manuals are just not useable at all.

ATR manuals are horrible.

As I mentioned in my above post, I've worked the structural side of maintenance my entire career. The B727 had a good SRM and was, from a structures point of view, a good plane to work on. However, it could make you so exasperated that you wanted to hand in your company badge and quit. One of these maddening items was the #1 and #3 engine pylon panels on the lower surface. Some of you mechanics may know of what I'm talking about. The panels were of a rudimentary composite design and had a special fastener and fastener receptacle to hold them to the pylon structure. The fasteners came in different lengths to match the area of the pylon panel they went through. If you didn't have the right length fastener, no luck getting it to catch in the receptacle and tighten up. To make it even worse, the receptacles were mounted on a long metal strip with 3/32" diameter rivets that were buried under the pylon structure. To get to a bad receptacle you had to remove all the panels under the pylon, remove the fasteners holding the strip, replace the receptacle, replace the strip back in place and reinstall the panels. Without fail, when you were putting up the panels, another receptacle would fail. I have spent two to three hours sometimes getting these panels back on the plane. I'm sure the engineers who designed this system did their best, but there were days when I would have liked to have had a talk with them out behind the hangar.
Gregory

gregorygoodwin wrote:

Some of you mechanics may know of what I'm talking about.

We called them hi-vibration fasteners and I remember them on the pylon, horizontal stabilizer panels and the aft wall of the bag bin forward of the mix manifold. For what reason did they put them in the cargo compartment?

Since were talking about the 727, who designed the E&E door? I don’t think I ever opened one without it coming off the tracks. The 737 was an improvement, but not by much.

LMP737 wrote:

Probably the biggest headache for me is the MD-11. Never mind the spare engine in the tail.

The eleven is a text book example of what happens when a manufacturer decides to cheap out. The plane is beset with all sorts of wiring issues. Why, because MD decided to use Kapton wiring when they built the thing. Even though by the time the -11 came to fruition the industry knew Kapton was junk. And now we get to deal with all the intermittent faults , shorts to ground, broken wires etc.

It has more than it's fair share of what the hell were they thinking moments. My all time favorite is the ant-skid shutoff valve design, of which it has two. One in each wheel well. Who ever was responsible for that system never heard of drip loops. That's because instead of having the electrical connector on the side with wiring going to it having a loop the connector is on the top of the valve.

A good video about Kapton wiring:

http://youtu.be/VZ_G9C0jwE8

MD wiring is such a mess compared to Airbus, Boeing,etc. I’ve seen better car stereo installations. When Boeing took over the MD-95, they fixed a lot of the wiring installations by adding connectors, plug in relays, insulated terminal strips and general neatness of installation.

gregorygoodwin wrote:

In my career in aircraft maintenance, I've always worked structures and composites. For me, the Lockheed L1011 had one of the best structural repair manuals. It was simple, straight-forward, and gave you clear and concise graphics and information.

Best Fault Isolation Manuals as well. Wire numbers had the ATA code of the system involved stamped on them. Fuel quantity tank probes that could be removed without entering the tank. Worlds greatest airplane to some, one of the worst by others (usually DC-10 technicians).

fr8mech wrote:

The LAMM is a sweet manual. About the only thing good about the aircraft.

Every wonder why the LAMM is needed? Because the AMM, the FIM and the WDM are just about useless for telling you what’s happening.

I’ve seen better D&O’s in Haynes Manuals.

The LAMM is a great manual. Just remember that it is not an updated manual to be used on the aircraft.

http://www.2040-parts.com/_content/items/images/52/1349052/001.jpg

hitower3 wrote:

Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help?

Yes they do.

A whole, big building next to LFBO is dedicated to customer technical service. A few hundred people working there.

The ground floor is, among other things, hosting the 24/7 AOG, quick response service, while the floors above contain large office open spaces.

In a nutshell, each open space is dedicated to one ATA chapter,
For example, you'd have the ATA 27 "flight controls" open space, with 10 or 15 offices, the walls are "decorated" with technical drawings and system schematics. The shelves are full of actuators and other salvaged ATA27 parts from every Airbus type.

At the beginning I remember asking something about the A350 spoiler arm mechanism was working and sure enough, they said "hold on", went to one of the shelves and handed me the whole damn spoiler lever with the functional mechanism. Museums would be jealous, really...

From what I could see A320 was a very reliable workhorse, not too many ongoing issues except the engines on the NEO versions.
A300 and A310 are getting old and have leaky hydraulics
A330 had some funky stuff happening in the hydraulic lines going through the engine pylon. It has been fixed by a non mandatory SB but not every operator did the upgrade/fix (IIRC)
A350 flies great but the IFE power supplies are, let's say, not the most reliable piece of equipment ever. I do not like the maintenance philosophy on that bird. Many many computers, it is loosing touch with the "hands on" parts of maintenance and troubleshooting. Less hydraulics, less pipes, less analog wires, more annoying software.

DL_Mech wrote:

The LAMM is a great manual. Just remember that it is not an updated manual to be used on the aircraft.

But there's the SSM which is an updated manual. It's 100% the LAMM, but digital and maintained by Boeing. Last revision date is 15 Jul 2021.

Genista wrote:

hitower3 wrote:

Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help?

Yes they do.

A whole, big building next to LFBO is dedicated to customer technical service. A few hundred people working there.

The ground floor is, among other things, hosting the 24/7 AOG, quick response service, while the floors above contain large office open spaces.

In a nutshell, each open space is dedicated to one ATA chapter,
For example, you'd have the ATA 27 "flight controls" open space, with 10 or 15 offices, the walls are "decorated" with technical drawings and system schematics. The shelves are full of actuators and other salvaged ATA27 parts from every Airbus type.

At the beginning I remember asking something about the A350 spoiler arm mechanism was working and sure enough, they said "hold on", went to one of the shelves and handed me the whole damn spoiler lever with the functional mechanism. Museums would be jealous, really...

From what I could see A320 was a very reliable workhorse, not too many ongoing issues except the engines on the NEO versions.
A300 and A310 are getting old and have leaky hydraulics
A330 had some funky stuff happening in the hydraulic lines going through the engine pylon. It has been fixed by a non mandatory SB but not every operator did the upgrade/fix (IIRC)
A350 flies great but the IFE power supplies are, let's say, not the most reliable piece of equipment ever. I do not like the maintenance philosophy on that bird. Many many computers, it is loosing touch with the "hands on" parts of maintenance and troubleshooting. Less hydraulics, less pipes, less analog wires, more annoying software.

You can also get engineering out (OEM or airline) to develop repairs or troubleshooting.

Genista wrote:

hitower3 wrote:

Does Boeing / Airbus have a "Tech Support Number" that you can call up and get help?

Yes they do.
A whole, big building next to LFBO is dedicated to customer technical service. A few hundred people working there.
.

I used to work on the Boeing corporate IT helpdesk in the early 2000s. If we got a call from an AOG group employee or anyone on the delivery flightline, we dropped everything to help them. They were our highest priority, even higher than executive support. Helping to get an aircraft back in the air, even indirectly, was the most important IT support request we could facilitate.

Any Aircraft which is Maintenance friendly is welcomed.
Ive worked on only the B737 & B757 last 32 yrs & found both to be good , easy Aircraft to maintain 95% of the time.

I'd say the hardest airplane I have worked on is the Piaggio Avanti, just plain difficult to work on, and those pusher engines came with their own problems, had to clean the prop blades every day with jet fuel, and the inside of the spinners looked like the inside of a woodstove from all of the soot. A close second to that is the Piper Cheyenne 3, another one we loved to hate as mechanics.

On the other side of the coin, probably my favorite aircraft to work on was the Dash 8-100. I liked that I could do most things myself, but it was big enough to be reasonably easy to work on. As for jets, I like the CRJ 900. I've never worked on large transport aircraft, so I figured I would put in my thoughts from the regional world.

Horstroad wrote:

DL_Mech wrote:

The LAMM is a great manual. Just remember that it is not an updated manual to be used on the aircraft.

But there's the SSM which is an updated manual. It's 100% the LAMM, but digital and maintained by Boeing. Last revision date is 15 Jul 2021.

Since loading Toolbox Mobile Library on my laptop there is just no way back....
bad thing is now I need to upgrade the laptop's harddrive.

Anyone have any experience with British built jets? I've heard that Hawker biz jets and the BAC 1-11 were notoriously bad.

Troubleshooting the PACK's on MD10/11's are always a fun time!