70

It's not duct tape. It's speed tape. Speed tape is an aluminum pressure-sensitive tape used to do minor repairs on aircraft and racing cars. It is used as a temporary repair material until a more permanent repair can be carried out. Probably just got a bit of a gap around the cowling or perhaps a loose fastener or two. It's common practice for sealing ...


65

Paint stripper. Lots of paint stripper. (originally I said thinner, but I have been corrected, it's more accurately called stripper) Seriously though, it's actually not too different to other things that you paint. You need to spray on paint stripper. But, just like when painting the aircraft, it's imperative that you cover up all the delicate systems on ...


55

With a few exceptions (modern aircraft engines with FADEC systems) a "Check Engine" light on an aircraft would be essentially useless. In a modern car we have an Engine Control Unit which manages things like mixture and engine timing. The "Check Engine" lamp illuminates when the ECU has detected a fault that requires some sort of attention, but it's not ...


54

It generally means that the hydraulic actuator (power control unit) driving the surface has an "idle" facility that allows fluid to move internally between the two sides of the actuator piston, or just circulate in the pressure/return lines, and when unpressurized it acts more or less like a hydraulic damper even though the input spool valve is at its "null" ...


53

Airliners are both larger and more complex than the small aircraft you're familiar with at your local flight school. For an example of some of the items to consider, see: What do you need to do to bring a 737 Max back in service after 6 months in storage? A lot of those things won't be improved just by flying the plane periodically, but some items are. ...


45

Because your basic premise is completely wrong. The people flying a Cessna or Cirrus generally have a vast amount more knowledge about their planes than the average car owner. Between the POH (Pilot Operating Handbook) and the general systems information that is part of every level of curriculum that level of knowledge of your average GA pilot is vastly ...


45

For unassembled and new planes or planes not yet painted the green/yellow color you see is the anti-corrosive coating on the aluminum ...every unpainted airplane is nominally green from being coated (typically) with an anti-corrosive green zinc chromate or zinc phosphate primer over the aluminum skins. The different shades of green simply tell you ...


44

Automobile engines are not similar. They are liquid-cooled and therefore can be built to much tighter tolerances with regard to thermal expansion and contraction. Air-cooled aircraft engines must deal with a large range of operating temperatures and oil is consumed due to the relatively looser fit of the piston rings.


43

South African Airways flights to 'less developed' locations in Africa often carry a mechanic and some spares on board. If there are no suitable repair facilities, supplies or maintenance personnel available at the destination, then their own guy can fix any minor mechanical issues. If there's a major problem then they would have to fly in additional repair ...


41

It doesn't quite work that way. When an engine wears out it's rated thrust doesn't decline; its "ITT Margin" (or some similar phrase - basically its thermodynamic margin at takeoff) declines. When setting takeoff thrust on a turbofan there is a target N1, or target torque on a turboprop or turboshaft, or Engine Pressure Ratio on a pure jet, and the engine ...


38

Although turbines could be designed to run on ethanol it's actually a lousy aviation fuel (actually it's a lousy fuel in general). Petroleum-based jet fuel is high grade kerosene which has lubricant properties, which ethanol lacks, and ethanol has different characteristics which mean you can't pour it in and use it as a replacement. Some problems with ...


38

Sure. In fact, the emergency slides have to be removed from aircraft and tested periodically under present regulations. According to Lufthansa Technik: Under current regulations each emergency escape slide must be removed from the aircraft every three years and checked in the workshop. The slide is tested by "flat firing" the slide on the floor; ...


36

For (modern) gliders with highly optimized laminar flow airfoils, bugs (or dirt) are a non-negligible factor, especially in competition gliding. There are some older laminar airfoils that are notoriously allergic to bugs (and rain), but all are to a certain degree. This is also the reason why any glider pilot worth his or her salt will painstakingly clean ...


32

All your plane's systems are happier when you're flying, including the pilot. Ideally, you'd fly often in order to keep your engine happy (distributing clean oil throughout the system to protect against corrosion and heating it enough to drive off water from the crankcase). As a rule of thumb Blackstone Labs (the oil analysis folks) consider piston engines "...


31

ETOPS stands for Extended-range Twin-engine Operational Performance Standards, a rule which permits twin engine aircrafts to fly routes which, at some point, is more than 60 minutes flying time away from the nearest airport suitable for emergency landing. ETOPS may also be interpreted as Engines Turn or Passengers Swim. It is not a rule which applies after ...


30

In addition to the chemical method in Simon's answer, there are mechanical methods, like bead blasting. This method was introduced in the 80s by airforces concerned with the volume of chemical waste generated by their maintenance facilities. It essentially consists of using compressed air to project fine plastic particles ...


30

As a generic answer, not unusual. Besides personal objects like bucking bars, clecos, rags and such left in tanks, the biggest contamination source, from my experience working on a production line many many years ago, is "swarf". Swarf is aluminum drill shavings and mountains of it are created during assembly. You will also get wire cutoffs and other ...


28

One of the main reasons why it's not a good thing to have dead bugs on the windshield is that it becomes very difficult to spot other traffic. Other planes are just little specks at a distance and when your windshield is covered with specks from dead bugs it becomes very difficult to spot another aircraft in the distance.


27

They have the usual transport options: shove into cargo area, on a flatbed truck, shipping container,... They can also be attached below the wing of a large aircraft and flown with if there is no room in the cargo area. (stolen from this question) Notice the extra engine on the near wing.


27

The doors are painted like this because it is a federal law that all cabin doors on commercial airplanes should be outlined in a color which contrasts with the fuselage color. It is done so that in case of an emergency on ground, rescue crew can find the doors easily and open them quickly. It happened in past years that passengers survived some crash ...


27

All of the 747-100/200 freighters I flew in the 1990s had FAKs (Fly Away Kits) aboard. I just checked a couple of the weight & balance data sets I still have from having done weight & balance work for one of them up until 2013, and the weights were 1967 and 1939 lbs. If the aircraft was a nose loader, the FAK was usually along the side of the in the ...


27

In my experience, having permanent airplanes standing by as spares does not really happen. Based on historical data potential realtime spares, airplanes with potential availability on any given day, can be pinpointed for reschedule or delayed maintenance, should the need arise. In reality, often the "spare" as you called it, is an airplane that can be ...


27

Perhaps this adds little to the answer already posted, but I feel it needs to be emphasized that airliners are designed to fly. Designed to fly a lot, in fact. Like, spend a significant portion of their working lives in the air. Southwest Airlines, for example, has each of its 737s in the sky for 9 hours a day. I imagine Ryanair's number is similar. And ...


26

I've heard it said that the break-even point for owning vs renting is 200 hours/year. I fly a lot less than that, but I don't like sharing my toys, so I own anyway. I make it a point to not actually count my cost of ownership, because it wouldn't be fun any more, but I'll give you some rough numbers. I bought a 1962 Mooney for \$30,000. That's about as ...


25

How do the engineers, maintenance team, etc know if an aircraft has metal fatigue? First of all, is not an "aircraft" that has fatigue, but a component. To the naked eye, there is no way to detect metal fatigue until it starts being too late: you can only see cracks that are already forming and/or propagating. There are tools available to allow for early ...


25

Cessna 150s have a mechanical tachometer driven by a mechanical tach drive cable geared to the engine. The tach needle is moved by sensing spinning magnets driven by the tach cable. They do wear out over time and yours has reached the end of its life.


24

If you can, you'll fly in maintance yourself to get it fixed, perhaps by chartering a cargo plane on the way. If you can land the aircraft, you can probably get any spare part in through the same runway, with varying degrees of difficulty. If it's bad, Boeing has an Aircraft On Ground team who should be able to fix pretty serious damage. Often, it may just ...


24

Some B-52s and other aircraft were put out of commission as part of the START treaties. They were dismantled in such a way that the Russians could verify this with satellite reconnaissance, just as in the photo above.


23

If the problem is a bad engine and the aircraft is a 747, the most cost effect solution is usually a 3-engine ferry to a repair station. From memory, the protocol to be observed includes: The Captain must do the flying. Only the cockpit crew can be aboard. The fan must be tied down to prevent it's rotation in flight. A specific takeoff procedure is to be ...


23

First, consider what a check engine light actually tells you. In short, it could be almost anything, which isn't very useful information. To find out what the specific problem is, you need to go to a garage and have a mechanic run a diagnostic check to determine what triggered the light. In a car, that's no big deal, but in an aircraft that's a huge problem:...


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