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30

The props are done before starting because you need to make sure the blades and spinners are fully cleaned off while they are stationary. Otherwise, they'd vibrate like hell when starting and shed bits of ice all over. Also, if you just sprayed the props while running the engines would ingest a lot of glycol, which, if it doesn't make the engine flame out, ...


29

Was it anything to be concerned No Should I have brought it to the notice of the airline crew? Yes, but not because it is a safety issue. Tell them so they can deal with it to give the next passenger a nicer experience. What is happening is no different than a glass of ice water sitting on your kitchen counter. The warmer side of the glass (the outside)...


23

The claim that de-icing must have been done perfectly in Brussels or the plane would have crashed on take-off is patent nonsense. Ice on the aircraft degrades performance. A little bit of ice degrades performance a little bit; a lot of ice degrades performance a lot. It's perfectly possible that they took off from Brussels with slightly degraded performance, ...


22

Putting this as an answer rather than a comment because of its length. In response to @romkyns comment, perhaps the 787 pilot knew of the heating elements within the wing but was simply telling how ice was normally handled. I really can't imagine him getting through his type rating oral without knowing that. Had you asked me the same question back when I ...


21

I'm not aware of any specific 'certification' for aircraft operating to/from Antarctica. The air operations to/from Antarctica varies greatly depending on the location of the airstrip and season. Actually, there are airports in Antarctica that can handle 'conventional' aircraft (atleast seasonally), like the Union Glacier Blue Ice Runway, which has been ...


20

Hot bleed air is drawn from the engines and directed through control valves and ducting to the leading edges of the wings and stabilizers. This is what it looks like on a 727. Note that the upper VHF antenna is also anti-iced to prevent ice entering the engine inlets. The 787 uses electric heating elements for the wing instead of bleed air from the engines....


18

You should definitely not attempt flight if there is frost on the windows that would affect visibility, or on any of the wings or flight control surfaces. Frost accumulation on such surfaces can reduce the lift generated by your wings, possibly causing a crash on takeoff. According to the NTSB, frost the size of a grain of salt, distributed as sparsely as ...


17

The wikipedia article already linked in the question says: The system uses power from the engines, thus reducing their maximum performance. With the anti-ice system on, the highest altitude at which the overloaded aircraft could fly – without stalling – was reduced to 31,900 feet (9,700 m). The de-icing system on most turbine aircraft (including MD-82 ...


17

Frost can be formed in two ways. On a colder object by water directly desublimating on its surface or on any object when air is saturated with water. Frost can form on a moving airplane, but only the second way. Why would they have anti-ice on pitot tubes, propeller and leading edges otherwise? When the air is not saturated with water, ice will sublimate. ...


17

There was a case where an easyJet Boeing flew through a hailstorm; the accident report is here, with a PDF download available, which lists some of the damage (which includes a cracked windscreen and damaged leading edges on wings and other surfaces). There are photos showing the damage incurred, including the one below. Search for "easyJet hailstorm damage" ...


16

It has to do with the local speed around the airfoil. In a canard configuration, the forward wing has to produce more lift per area than the main wing in order to have natural longitudinal (or pitch) stability. This means the suction is more intense, and the pressure on the upper side of the airfoil right behind the leading edge is lower than on the main ...


16

It does, but there is much less of it on the fuselage than on the wing. There are two ways how ice is accumulated on the aircraft's structure: When flying through air containing supercooled water droplets, the water will freeze on impact. It does not make much of a difference whether the water impacts the fuselage nose or the leading edge of the wings and ...


16

Versalog already told the core of the thing. Most prop aircraft which are approved for flights into known icing conditions have such boots to remove the ice from the wings leading edge. Those boots are either inflated manually whenever you need them (by the press of a button of course), at regular intervals or automatically whenever ice is detected. Check ...


15

Frozen precipitation comes in many forms Hail Graupel Sleet Snow Freezing rain (technically supercooled and not frozen) Of these, hail and freezing rain are the biggest threats to aircraft and I'll focus on hail as that seems to be the topic of your question. Hail, especially "brick sized" hail require very strong updrafts in severe thunderstorms to be ...


15

When operating under Part 91, taking off with an iced windshield is not permitted. It does not differentiate between IFR and VFR operations. § 91.527 Operating in icing conditions. (a) No pilot may take off an airplane that has frost, ice, or snow adhering to any propeller, windshield, stabilizing or control surface; to a powerplant installation; ...


15

I don't know if you're in the US, but if so then by regulation you must remove it from all critical areas before flight, per 14 CFR 91.527: §91.527 Operating in icing conditions. (a) No pilot may take off an airplane that has frost, ice, or snow adhering to any propeller, windshield, stabilizing or control surface; to a powerplant installation; ...


15

It depends on the severity of the hailstorm. In the event of encountering large hail pieces in the sky during cruise, a pilot will generally try to climb above the storm (of course with ATC permission) to prevent damage to the airframe. However, it is always better to stay out of the hailstorm in the first place and pilots will usually try to negotiate a ...


12

Usually, no. There are two main methods used to deice an airplane in the air. One is letting warm air that is bleed from the jet engine to heat the wing leading edge. The other is to have have rubber air bladders (called deice boots) on the leading edge of the wing and tail surfaces that are pumped up and the ice falls off. Both of those methods are only ...


12

Find a picture of any WWII bomber or any modern Cessna Caravan and there should be a black stripe along the leading edge of the wing and tail surfaces. That is termed a boot. (Image source) Inflating it slightly will make the ice break and fall off the wing.


11

"Icing conditions" is a pretty vague term that encompasses a lot of various situations that can cause airframe icing (AOPA pdf report, so it's hard to have one definitive answer. That said, you can expect to accumulate some degree of ice when flying through moisture (clouds, rain, etc) when outside air temperatures (OAT) are near or below 36°F / 2°C. Also as ...


11

When you close the throttle for descent, the airflow is constricted. This constriction is going to cool the air more than it is during cruise configuration, and may increase icing. From This AOPA document: Throttle ice is formed at or near a partly closed throttle valve. The water vapor in the induction air condenses and freezes due to the venturi effect ...


11

The icing occurs due to the presence of supercooled liquid droplets. From FAA AC on Icing: The condition most favorable for very hazardous icing is the presence of many large, supercooled water drops.... Thus, heaviest icing usually will be found at or slightly above the freezing level where temperature is never more than a few degrees below freezing. ...


11

Short Answer: Yes, pilots frequently see this phenomenon. No, it does not necessarily present a specific icing hazard. Yes, in some circumstances it can be in indication of an icing hazard. Longer Answer: Speaking for myself, yes, I often see this. I cannot speak for all pilots, but I think many pilots do also see this. The phenomenon depends on several ...


11

It appears that there was a considerable amount of contamination, either snow, ice, frost, or a mix thereof, on the wing when the takeoff roll started, and that is not considered safe under any current standards I'm aware of. There are markings on the top of the wing for the 737 Next Generation series that define an area where cold-soaked fuel frost is ...


11

While there may be guidelines as to whether to climb or descend when you're icing at your current level, individual pilots that I have known varied widely in the specifics of what they would do depending on their experience, their comfort level in icing, the route they were flying, and their experience with that route in bad weather. My take follows. First, ...


11

There are many things you can do to mitigate the risk of icing, but most involve prevention via avoidance of icing conditions. For example, getting a good weather brief, knowing where the freezing level is, staying away from visible moisture, and finally, recognition and taking evasive action. Pre-flight deicing liquids are not intended to prevent ice ...


11

Generally light GA aircraft have limited anti ice system, usually limited to just pitot heat. Some newer aircraft have been certified for flight into known icing (FIKI) and make use of chemical deicing methods like TKS “weeping wings” or electrically heated systems like the Kelly ThermaWing. I will caution you that, even if your aircraft is FIKI certified, ...


10

Some airplanes don't need the horizontal stabilizer to have anti-ice because it was shown during flight testing that there were no adverse effects from having ice on the tail. This is mainly because the horizontal stabilizer/elevator has been designed so that even with a degradation of lift due to the ice, it still produces a sufficient tail down force to ...


10

Apart from pumping hot air, there are a few ways to achieve wing's leading edge de-icing. Most reliable is through electric heaters just beneath the wing surface. Other are more tricky. One solution is an elastic leading edge, which can be pushed out by, for example, a linear hydraulic motor. If the ice thickness is just right, it will crumble and fall off....


10

If you feel that you would need carb heat sitting on the ground, I'd recommend taxing back and waiting for conditions to improve. If you are set on going, usually doing a run-up at the runway before take-off will tell you if you have carb ice or not. The other answer gave good reasons, sucking in some FOD (foreign object debris), but there are some other ...


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