71 votes
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Instrument landing: why do all electronic devices need to be shut off?

Short answer: ILS is rather sensitive to interference and not all electronic devices take much precaution in avoiding the generation of interference. The pilot wants to be sure that the readings he's ...
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64 votes
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Why does flying IFR require a rating?

The short and sweet answer to this question: That kind of thinking is what kills a lot of pilots. A non-instrument rated pilot may know how to fly and navigate but does not yet have the skill to do ...
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39 votes
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What happens when a pilot has no Instrument Rating and visibility drops?

It is very rare for weather to go IMC unexpectedly. A responsible pilot should see that weather is deteriorating, and begin planning for the nearest available landing. If they cannot find a landing,...
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  • 28.4k
39 votes
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Was it possible to land a Boeing 707 with 300 feet cloud ceiling in the 70s?

ILS approaches were in common use in 1970 when I got my instrument rating. The normal (Cat I) ceiling minimum was 200 feet. So, yes, a 707 would have been able to land with a 300 foot cloud ceiling in ...
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  • 38.7k
33 votes
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Why is a clock necessary for IFR?

There are several reasons: For departure clearances. An IFR clearance may have a void or release time so that clearance is only valid between certain times. For holding pattern legs. A standard ...
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  • 70.3k
31 votes

Why does flying IFR require a rating?

Because it is very difficult to navigate with instruments alone. I just wished to illustrate to you by giving you an example. (These are flight simulation images, but should illustrate the idea well.)...
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31 votes
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Am I allowed to tell ATC "unable" if asked to climb to less than 12,500 ft without supplemental oxygen aboard?

FAR 91.211 only requires supplemental oxygen be used by the pilot/minimum required flight crew for that part of the flight at altitudes above 12,500 MSL to 14,000 MSL that is of more than 30 minutes ...
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  • 18.7k
30 votes
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Why fly VFR at all?

(This answer is based on light aircraft in the US.) Leaving aside any scenarios where you must file IFR (class A, IMC) and any where you can't (pilot and/or aircraft not IFR-capable), it comes down ...
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  • 70.3k
28 votes

What happens when a pilot has no Instrument Rating and visibility drops?

A visual pilot flying into instrument conditions is a serious emergency. It's much better to avoid the situation in the first place which is why there's a significant amount of training around ...
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  • 49.6k
26 votes

Why does flying IFR require a rating?

Once in the air, the pilot's most basic task in manipulating the controls is to keep the airplane right side up. As it turns out, this is much easier to do when we have reference to an outside real ...
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  • 38.7k
26 votes

How do pilots align the HUD with their eyeballs?

The other way around - you set up the pilot for eye-to-HUD alignment. When you are in the right position then you can see all the data-fields on the HUD - if you can't see them, you move your seat.
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  • 4,467
25 votes
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Is the pilot required to keep visual lookout during IFR operations in VMC?

You didn't mention which country or jurisdiction you're asking about, but in the US 14 CFR 91.113(b) says: When weather conditions permit, regardless of whether an operation is conducted under ...
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25 votes
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Is there a penalty for changing the approach procedure after accepting one?

There is no penalty per se, but visual approaches in particular have lower separation requirements, so having to switch you back to a non-visual approach may require ATC to make corrections (e.g. ...
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  • 26.4k
24 votes
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What are the reasons for autopilot restrictions on instrument approaches?

It's the fact the autopilot works more accurately than a pilot which is actually the cause of the restriction. The decision to restrict the use of the autopilot usually comes from the certification ...
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24 votes
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How many holds to be IR current?

According to this AOPA article, quoting the FAA person who actually wrote 61.57, it’s one hold: When paragraph 61.57(c)(1)(ii) [i.e., "Holding procedures"] was written it was not intended ...
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  • 70.3k
23 votes
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May a non-instrument pilot legally file IFR as long as he amends and doesn’t accept an instrument clearance?

My instrument students, when they get more advanced, file FP with their name, and in remarks say "Training xxxxxx CFII" That way it is clear. The FAA office investigated one student, dug up his ...
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  • 17.4k
23 votes

Why do helicopter operations avoid IFR?

Helicopters do not avoid IFR. They will, however, try to avoid IMC for safety reasons. The same is true for airplanes in the same weight class. Just because the pilot is IFR rated and the aircraft is ...
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  • 16.2k
22 votes
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What is the purpose of VFR-on-top?

The VFR on top clearance is often given with a block of altitudes. Such as this from the reference document "Maintain VFR-on-top at or between six thousand and one zero thousand.” With this ...
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  • 1,294
21 votes
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Is skydiving in IMC (through clouds) legal and safe?

It is not legal to conduct skydiving into clouds, atleast in US. From 14 CFR §105.17 Flight visibility and clearance from cloud requirements: No person may conduct a parachute operation, and no ...
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21 votes
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Why must IFR be cancelled?

It's all about making sure everybody knows what's going on. While you are on an instrument approach and thus flying IFR, ATC is responsible for spacing you, giving instructions on heading and speed in ...
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  • 22.3k
21 votes
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How do pilots align the HUD with their eyeballs?

A pilot will usually adjust his seat height to align his eyes roughly with the design eye-position in an aircraft. As there is almost no parallax error, even with the wrong seat height, HUD-elements ...
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  • 105k
20 votes

Instrument landing: why do all electronic devices need to be shut off?

Having worked as a software engineer on the lateral guidance subsystem of the FMCS (Flight Management and Control System) for the Airbus A310 about 30 years ago I found @reirab's answer fascinating. ...
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19 votes

Instrument landing: why do all electronic devices need to be shut off?

You can read this related question if you want to learn more about the interference between electronic devices and airplanes. An answer there links to a very good document written by NASA on the ...
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  • 1,655
19 votes
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What coming changes might render current IFR equipment worthless in the foreseeable future?

At the moment the answer is "None" - with two exceptions: LORAN receivers These are already worthless because the US has shut down our LORAN chains. They are jokingly referred to as "IFR-Certified ...
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  • 67.2k
19 votes

When are procedure turns not required?

The correct thing to do very much depends on the clearance that you were given. If you were simply cleared direct to BEJCY and cleared for the approach, then your instructor is correct and you should ...
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  • 57.6k
19 votes

Why are visual approaches (in the US) preferred by US pilots, but not European pilots?

Since your question explicitly mentions emergency situations: Especially during time-critical emergency landings, the workload of the flight crew is at a higher level anyway. The answer by ymb1 ...
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  • 1,186
18 votes

Intercepts and aerial combat in IMC (or my no-fly zone is full of clouds?!)

In the first scenario, where it sounds like you're assuming that the intruder aircraft is known to be hostile even without seeing it, a shot with a radar missile would be unaffected by the IMC, and ...
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  • 41.9k
18 votes

If you were to fly an ILS in a knife edge would you receve GS and LOC be flipped?

No, the directional part of ILS is located at the ground. (Ground) transmitter creates lobes with specified frequency and modulation to mark the high, low, right and left areas. LOC and GS signals ...
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  • 2,379
18 votes

Why do helicopter operations avoid IFR?

Helicopter IFR operations do exist, but the short answer to the thrust of your question is: helicopter IFR is inherently more dangerous than fixed-wing IFR due to the lack of stability. A properly ...
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