Not certain, but I have heard of aircraft being scrapped/sold because of the cost of a D-check. If there's a level above that, it must be above the equivalent of what the Navy do to carrier-based aircraft. And I can't see an airline sucking down a cost like that so I don't believe it exists.
I believe that A-Checks are the day-to-day stuff (tyre kicking if you like) and that B-Checks are every few months.
I equate this to the following car analogy;
A-Check: Fluid levels, (oil, coolant) obvious leaks. Maybe tyres.
B-Check: Oil leaks, smokiness, brake pads and discs, light bulbs (that last one is probably on the aircraft A-Check)
C-Check: Steering rack, hoses, filters, aircon if fitted.
D-Check: Cam belt/chain, structural integrity and welds, paintwork, suspension, CV boots, fuel system, airbags, etc, etc, etc...
It's not quite analogous since a car will happily bimble along with faults that a plane would not, but I think that's the idea.
Fr8Mech From United States of America, joined Sep 2005, 4719 posts, RR: 12 Reply 4, posted (6 years 4 months 3 weeks 1 day 9 hours ago) and read 3773 times:
This has been discussed here before. Perform a search.
Basically, maintenance checks and intervals are set by the operator in conjunction with the manufacturer and the regulatory body.
We, for example, have:
Arrival service checks, daily
Periodic service checks, approximately weekly
After that, our requirements diverge by fleet. Some aircraft get A checks, interval determined by aircraft type. Some get Phase checks and some get higher (numerically, PS2, PS3, etc) Periodic Service Checks.
After that, they all kind of converge into 'C' checks. 'C' checks, for us, also incorporate part of the 'D' check package. This eliminates the need for a 'D' check, but keeps the aircraft out of service for a longer time at 'C' check.
In short, the answer to your question is, it depends on the aircraft, the operator and the government.
Quoting Captainsimon (Thread starter): Also on a flight last week whilst at the gate an engineer drove up to the A321 opened up the engine side cover and put a can of something in each of the engines.
Oil. Though modern jet engine do NOT consume their oil, normally, you will have to top them up occasionally, just like you car. Oil consumption, on newer engines, especially ETOPS certified engines, is measured in fractions of a quart per hour.
DALMD88 From United States of America, joined Jul 2000, 2442 posts, RR: 15 Reply 8, posted (6 years 4 months 3 weeks 1 day 8 hours ago) and read 3747 times:
The names of the checks can be different for different operators so it can be confusing. At DL we do transit checks at every overnight MTC station. I think a plane needs one at least every three days. Next up the scale is a Layover check. I don't know the frequency, maybe weekly. Next is a service check which I think is on a 250 flight hour interval. After that some get Letter check(MD88) others go to PSV checks which are also hour driven and occur at about 18 month intervals. Some fleets; 738, and 777 have used the PSV system to completely replace the overhaul/ D-check. Our 767 and MD-88/90 fleet still get overahaul at the end of the PSV/Letter check cycle which I think take five years.
Yes, the mechanic was adding oil to the engines. Some engine types use a lot of oil. The CFM56 can use 4-6 quarts in a cross country fllight.
As others have said search this forum for this topic. This question is very common and there are some very detailed answers in the archives.
I know that would make sense, but that is what our program calls the most basic check. I believe we are required to do one if a plane sits at a MTC base longer than six hours. So every overnight aircraft gets one. It is a real simple check; tires, brakes, fluids, oxygen, clean windsheild, walkaround, and a walk through the cabin. You don't even check emergancy equipment in the cabin. I usually do check for it to all be there and for required safety seals.
HAWK21M From India, joined Jan 2001, 31450 posts, RR: 57 Reply 12, posted (6 years 4 months 2 weeks 6 days 20 hours ago) and read 3606 times:
Quoting DALMD88 (Reply 11): I know that would make sense, but that is what our program calls the most basic check. I believe we are required to do one if a plane sits at a MTC base longer than six hours
What is your Transitting Aircraft check called.
Xv408 From United Kingdom, joined Nov 2006, 52 posts, RR: 0 Reply 13, posted (6 years 4 months 2 weeks 6 days 12 hours ago) and read 3586 times:
Quoting KELPkid (Reply 1): Jet engines consume their oil, they don't have a closed lubrication system like a piston engine
I think you'll find that commercial engines are closed systems. If not, the oil tanks would be gargantuan.
The only open system I can think of was the Bristol Orpheus, which was designed as a target drone engine and therefore had no life and a short flight time. Making it a open system reduced cost and complexity of a scavenge system.
I guess there are several other examples in a similar light.
For a nonETOPS aircraft they used to called through flights. There isn't any actual through flight check in our paperwork. A mechanic just goes out and meets the plane to take care of any issues the crew has. I personally don't do many of these, due to my work hours. Maybe once every couple of weeks I get assigned one of our redeye inbounds near the end of our shift.
I'd swear, back when I was a widget, these were called Transit Checks. But then again, I was doing a lot of contract work on JFK at the time along with my work on LGA. Might have some operators mixed up.
TristarSteve From Sweden, joined Nov 2005, 3855 posts, RR: 34 Reply 17, posted (6 years 4 months 2 weeks 5 days 7 hours ago) and read 3489 times:
Quoting HAWK21M (Reply 16): Quoting Fr8mech (Reply 15):
I'd swear, back when I was a widget, these were called Transit Checks
Out here its called Transit check/Preflight check.
Nearly all operators of short haul aircraft in Europe do not have mechanics meeting transit aircraft. The pilots do the walkround and the refuelling. If the pilots need help they call someone and a mechanic shows up.
On ETOPS aircraft a transit check by a mechanic is required, and we do them on B747 as well.
The first required inspection on the shorthaul fleet is a Daily check, which is carried out every nightstop, and at least every two days if the aircraft doesn't nightstop.
HAWK21M From India, joined Jan 2001, 31450 posts, RR: 57 Reply 19, posted (6 years 4 months 2 weeks 5 days 1 hour ago) and read 3473 times:
Quoting TristarSteve (Reply 17): Nearly all operators of short haul aircraft in Europe do not have mechanics meeting transit aircraft. The pilots do the walkround and the refuelling. If the pilots need help they call someone and a mechanic shows up.
Out here,Pilots only certify Transit checks for Weather related diverted Aircraft,due non presence of Licenced AME,provided there is no Snag present.Although CAR-145 permits Pilots certifying Transit checks of certain category Aircraft,but most Airlines have not gone along with it.
A/c train From United Kingdom, joined Jun 2001, 501 posts, RR: 4 Reply 20, posted (6 years 4 months 2 weeks 4 days 13 hours ago) and read 3442 times:
PART-145 APPROVAL IS NOT REQUIRED FOR A PRE FLIGHT CHECK, thus a licenesed engineer need not sign. That is a factual statement ! Flight crew are not allowed to sign an ETOPS check, however they can sign a pre-flight check, so , why spend money basing an engineer down route when you dont need one?
TristarSteve From Sweden, joined Nov 2005, 3855 posts, RR: 34 Reply 22, posted (6 years 4 months 2 weeks 4 days 10 hours ago) and read 3428 times:
Quoting Starlionblue (Reply 18): Quoting TristarSteve (Reply 17):
If the pilots need help they call someone and a mechanic shows up.
POOF! Out of thin air!
If you are lucky!
We have company engineers at some stations, contract engineers on call at some, and at stations where there is less than one flight a day, we usually have no-one. The engineer has to be flown out from base!
10 years ago there was an engineer on every transit. Now when I go on board one of our aircraft, usually to pick up some English papers, or get a breakfast, the crew are surprised to see me.
DALMD88 From United States of America, joined Jul 2000, 2442 posts, RR: 15 Reply 23, posted (6 years 4 months 2 weeks 4 days 5 hours ago) and read 3407 times:
Quoting HAWK21M (Reply 16): There would be an official term.What does the Document signed read
There is no document. We don't have check for through flights. A mechanic is assigned to each inbound flight in case one is needed. If there is no inbound 'I need a mechanic' call you don't have to meet the flight. If your not busy doing another task you do go out and walk around it to try and catch anything the crew might find on a walk around. If you do anything like oils, it goes in the book, otherwise nothing goes on paper.
Now an ETOPS flight would be different. We don't get them at my station, so I'm not familair with the Predeparture Check.