Trick Questions

[Colonel Sanders]

Perhaps I am alone on this, but I firmly believe
that trick questions DO NOT belong on the PPL,
CPL or (gasp) IFR written tests.

Here is an example of a good written test question,
that measures PPL-level aviation knowledge:

In a traditional light single engine trainer aircraft equipped
with a vacuum pump, what instruments could you expect
to malfunction after a complete electrical system failure?

1) airspeed indicator
2) altimeter
3) attitude indicator and heading indicator
4) gas gauges and turn co-ordinator

And here's a terrible question:

An eighteen wheel truck and trailer is driving down
Highway 401 at 113 kph. It is filled with twenty thousand
chickens, all of whom suddenly (and at the same time) jump
up into the air and flap their wings before landing again 2.36
seconds later. How will the weight of the entire truck &
trailer be affected?

1) not at all
2) heavier
3) heavier, then lighter, then heavier again
4) lighter, then heavier, then lighter again

See the difference? A PPL should know the answer to
#1 - basic systems knowledge. He does not need to
ever know (or care) about #2.

[FenderManDan]

Dear CS, you are not alone. Those trick questions are product of bored semi comunist minds

[lownslow]

I've been lucky with my exams (glider on up through fixed wing ATPL), none have had any such trickery. I always just assumed the people who complained about trick questions never actually read the question or answers all the way through.

LnS.

[iflyforpie]

All you ever needed to know about your four choices on a Transport Canada exam question. Take it from someone who has written 14 aviation exams (10 for AME M1 and M2 plus PPL, IFR, CPL, and IR) and failed none of them.

a) An absolutely ridiculous answer.

b) The answer you would get if you omitted a step or had a transcription error or some other brain fart.

c) A correct answer.

d) An answer that is more correct than the other correct answer.

[CpnCrunch]

Is that chicken question really in the PPL? What is the correct answer? I would imagine they want answer [1], although I don't think that is correct. Although the mass will remain the same, the downward force on the tires will change (the same as if you jumped up and down inside the truck). What is their definition of "weight"? Anyway, it's a silly question.

[PilotDAR]

I once wrote a TC exam, which of course had two very wrong answers. One of the possible two right answers was an impossibility of physics, while the other one was a violation of air regulations if carried out. Thus, I concluded that the "more correct" answer was the one which did not involve violation of air regs. Wrong me, the correct answer was the violation of an air reg. So, I objected, and the outcome reversed.

Interestingly, for a 30 question helicopter exam, 10 questions had nothing whatever to do with helicopters, so that was a bit tricky too....

[Colonel Sanders]

Is that chicken question really in the PPL?

No, but don't give them any ideas.

Anyway, it's a silly question

Yes. Despite what some might think about it
measuring fundamental understanding of aerodynamic
principles.

[TopperHarley]

I remember on my CPL exam one of the questions was "what is the approximate climb rate of migratory birds" or something along those lines. One time I was reading through the AIM and I came across the answer and couldn't help but laugh. What a waste of a question.

[Colonel Sanders]

Here's a really nasty trick question, that I actually
encounter from time to time in real life:

You are going to reposition an airplane with a single
600hp R-1340 engine from one airport to another. The
duration of the flight is 30 minutes. What is the minimum
number of US gallons of fuel must you have on board to be
legal for the day VFR flight?

1) 30
2) 45
3) 55
4) 37.5

This is a nasty trick question, but at least it's on a useful
topic - running out of fuel, a popular cause of accidents.

[Big Pistons Forever]

Here's a really nasty trick question, that I actually
encounter from time to time in real life:

You are going to reposition an airplane with a single
600hp R-1340 engine from one airport to another. The
duration of the flight is 30 minutes. What is the minimum
number of US gallons of fuel must you have on board to be
legal for the day VFR flight?

1) 30
2) 45
3) 55
4) 37.5

This is a nasty trick question, but at least it's on a useful
topic - running out of fuel, a popular cause of accidents.

Lets see full power = 60 GPH, climb = 45 GPH, Cruise = 30 GPH. So 30 gals to start,taxi,takeoff, climb and cruise to get you to your destination plus 30 more mins at 30 gph = a total of 45. B is therfore my answer.

[CpnCrunch]

In theory you don't need to do a run-up, and you can in theory cruise at 100ft if there is nothing in the way. So minimum is 15 gallons for cruise and 15 gals for the 30 min reserve = 30 gals total, so [1] is my answer. If I was actually flying it, I'd like to have a bit more though

Having never flown an R-1340 I'm sure there is something I'm missing and I've probably got the wrong answer.

[Colonel Sanders]

You guys are doing pretty darned good, but
I want to draw your attention to:

602.88

(3) An aircraft operated in VFR flight shall carry an amount of fuel that is sufficient to allow the aircraft

(a) in the case of an aircraft other than a helicopter,

(i) when operated during the day, to fly to the destination aerodrome and then to fly for a period of 30 minutes at normal cruising speed

I agree that you could fly the 30 min trip at 50% power
(30 gph or 15 gallons) but is 50% power really "normal
cruise" IAW CAR 602.88(3)(a)(i) or slow cruise, when
considering the reserve fuel requirement?

Believe it or not, this question is more about interpreting
and applying the VFR reserve fuel requirements of the CARs.

I told you it was a nasty trick question. If it's any
consolation, it's on a useful topic, unlike most nasty
trick questions

Having never flown an R-1340

Doesn't matter. You figured out what you needed
to, about it. Hardest thing is starting it in cold wx.

Hint: (c) or (3) is wrong. I put 55 gallons in there
simply for nostalgia - wrestling 55 gallon drums around,
and for the wise-asses that always guess the third
answer.

[Meddler]

Well, if you're fueling from drums then one drum is the correct answer. Unless you need more than one drum, in which case....two drums.

No sense leaving partials laying around.

[Colonel Sanders]

I suppose (c) is the quantum answer ...

Anyways. It's a favorite nasty trick question of mine,
because it tests your knowledge not only of BSFC
but also of the legal definition of reserve fuel.

A better testing technique would be to break it
up into two questions, one on each subject.

Here's a better CAR 602.88 question:

Your airplane burns 10 gph at 50% power,
and 13 gph at 65% power. You need to reposition
the airplane to an airport 30 minutes away using
the 50% power setting. What is the minimum number
of US gallons you must have on board for this day
VFR flight?

[photofly]

It doesn't say "at the same speed". I think it means "a" normal cruising speed. And I normally cruise at 50% power anyway.

[Colonel Sanders]

IIRC people have taken trips to the Tribunal to discuss
this very topic ... PF, you want to dig them up?

For example, you fly someplace at 65% power, but your
30 min day VFR fuel reserve is calculated on 50% power.

Hmm.

[Colonel Sanders]

Here's a more real world question:

A friend of yours points at his 300hp C185 and
tells you to take it up for a flight. You have never flown
a C185 before, but you note that it has 10 gallons of fuel
on each side. What is the longest legal day VFR trip you
can take, at 50% power slow cruise?

Hint: solve for Z:

20 = Z x (50/100 x 300/10) + (30/60 x 65/100 x 300/10)

Do it in your head.

PS It's funny how people think you need to take an engineering
degree to learn how to solve partial differential equations, to learn
how to fly an airplane, when in fact what you need to learn to do
is grade-school arithmetic in your head.

Doesn't matter what kind of airplane I jump into - could be a PT-22
Ryan, could be a Pitts, or 421, could be an L39 - these are exactly the
kind of calculations I do in my head before I crank.

[photofly]

Woods vs. Minister of Transport CAT File No. P-1908-02 is peripheral to the issue; note that 602.88(4) which refers to IFR fuel reserves doesn't say "at normal cruising speed" - it just says, in addition to the part about missed approach and flight to the alternate aerodrome "fly for a further period of 45 minutes".

On the subject of minimum fuel, both IFR and VFR flights are required to comply with 602.88(5) which says

(5) Every aircraft shall carry an amount of fuel that is sufficient to provide for

(a) taxiing and foreseeable delays prior to take-off;

(b) meteorological conditions;

(c) foreseeable air traffic routings and traffic delays;

(d) landing at a suitable aerodrome in the event of loss of cabin pressurization or, in the case of a multi-engined aircraft, failure of any engine, at the most critical point during the flight; and

(e) any other foreseeable conditions that could delay the landing of the aircraft.

That might be more than 602.88(3) - VFR or 602.88(4) - IFR reserves.



By the way: 602.88(3), 602.88(4) and 602.88(5) are standards, not regulations. They should be moved to 622.88. I will write to TC right away.

[jump154]

Just for fun I gave my Air Cadets a unit test where most of the answers were the same (D I think) - it made the smart ones extremely uncomfortable. To add to the merriment the second last answer was something other than D, they didn't like that.

[Colonel Sanders]

602.88(3), 602.88(4) and 602.88(5) are standards, not regulations. They should be moved to 622.88

Would that bring into question their validity?

[Big Pistons Forever]

Just for fun I gave my Air Cadets a unit test where most of the answers were the same (D I think) - it made the smart ones extremely uncomfortable.

That is just evil

On second thought you should edit your post, we don't want to give TC any ideas

[Shiny Side Up]

Perhaps I am alone on this, but I firmly believe
that trick questions DO NOT belong on the PPL,
CPL or (gasp) IFR written tests.

Here is an example of a good written test question,
that measures PPL-level aviation knowledge:

In a traditional light single engine trainer aircraft equipped
with a vacuum pump, what instruments could you expect
to malfunction after a complete electrical system failure?

1) airspeed indicator
2) altimeter
3) attitude indicator and heading indicator
4) gas gauges and turn co-ordinator

I hate to point out to you the heavy irony present here in that you've asked a question that would stump a fair number of new PPLs, and that they would consider a "trick" question. Given that consideration I certainly don't envy anyone making such tests.

First trick: What is a "traditional" light single engine trainer? Does that mean tube fabric taildragger? Does it mean aluminum Cessna? or are we talking about a plastic Diamond?
Second trick: Why do you specify vacuum pump when this is clearly a question about the electrical system?
Third Trick: What do you mean by complete electrical system failure? Do we still have battery power?

Being tricksy I tells ya'. Different answers given different considerations. Either way, the point is that to really eliminate any question over what the correct answer is, you must be a lot more specific, which is going to require a longer worded question, and we know how potential pilots feel about reading more. I would guarantee that even what you view as a simple straight forward question, at least half of the potential PPLs out there would have issue with, especially if someone didn't sit down with them (or said question and correct answer) and make clear the assumptions present.

At the end of it, some subjects really aren't written test type questions. It belongs heavily in the practical testing regime. Systems knowledge, meteorology, and flight planning fall into this category. I would happily see flight tests extended if we could omit these sections from the written. The written test should really focus on the CARs and stuff that as pilots one should consider critical need to memorize knowledge. The way things are done though are because we hate to admit that as bad as the written test may be, most of the populace would feel it horribly unfair if they were to be grilled on said knowledge it tests in person and it being laid to judgement of said person.

Its all about everything being fair right?

[photofly]

Would it still be a fair question if the candidate had only ever flown a G1000-equipped aircraft, like a new 172?(http://www.cessna.com/single-engine/skyhawk)

Would it be fair to ask a candidate who had only ever flown a steam-gauge aircraft what instrument indications would be lost on failure of the flux gate magnetometer?

I don't think I have a good answer to that.

[Shiny Side Up]

My point exactly.

We're stuck with said written test though, because a 25% chance of getting an unfair question right is viewed as more fair than having someone in person tell someone their wrong in their judgement. That way we can blame the big bad government when someone doesn't know stuff rather than a mean ol' examiner. Part of the reason the flight test is so watered down too.

[Colonel Sanders]

I am happy to hear that all ab initio flight training
in Canada is now performed in glass cockpit trainers
like the Cirrus, and that all those old six-pack Cessnas
and Pipers have been scrapped and no one flies them
any more.