Questions from my Mailbox
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I get a lot of e-mail asking questions that aren't answered on this
website
yet. I'm going to put the questions and answers here, to save myself
from
having to answer the same question more than once. It's not like they
are
asked frequently, but one good question deserves an answer. I'll
organize
this later, but meanwhile, in more or less the order you asked me ...
Altitude
| Private Pilot
Written
Exam | METAR |
Life
Insurance | Visiting Canada | Flying in BC | Flying in the US
| PSTAR Error? | FDRs | Gust loads | Landing | Other
What
is QNH or QFE?
QNH is British for what Canadians call "altimeter setting": the numbers
to
set in the little window on your altimeter to make the altimeter
correctly
show your height above sea level. QFE is the altimeter setting that
makes
the altimeter read ZERO at touchdown. The British military use QFE;
perhaps
because they can't do addition well enough to calculate the circuit
altitude
without it. You can find more Q-codes at http://www.kloth.net/radio/qcodes.php.
What is
MSL?
MSL stands for "mean sea level" and is the American equivalent
of ASL. We say 1500' ASL; they say 1500' MSL. There is no difference in
meaning.
What is the difference between
Density
Altitude and Pressure Altitude?
First the definitions:
Pressure altitude is the altitude that would show on
your
altimeter if you set 29.92 in the subscale window.
Density altitude is pressure altitude corrected for
non-standard
temperature.
Now the explanation of what that means:
You know about the international standard atmosphere (ISA), right?
Imagine
a column of air that has ISA conditions: 15 deg C and 29.92" Hg
pressure at
sea level, and then temperature decreasing 1.98 degrees and pressure
decreasing
1" for every 1000' feet you go up. Consider this atmosphere..
Your pressure altitude is the altitude you would have to be at in the
ISA
in order to experience the pressure you are experiencing at your
altitude.
You know that air temperature affects your performance. The
hotter it
is, the poorer the performance. If the temperature is higher than
standard
temperature, as far as your airplane is concerned, it is the same as
being
at a higher altitude.
Your density altitude is the altitude you would have to be at in the
ISA in
order to get the same performance as you get at your own pressure and
temperature.
Now how to figure them out:
There are two ways to figure out pressure altitude.
A. Set your altimeter subscale to 29.92, and read the pressure altitude
off
the altimeter.
or
B. Subtract your altimeter setting from 29.92. Multiply the result by
1000.
Add the
result to your elevation or indicated altitude.
To figure out density altitude:
1. Calculate your pressure altitude, using A or B above.
2. Set your pressure altitude opposite the air temperature in the
little window
on the inside of your E6B. Notice that the temperature scale goes
backwards.
3. Read the density altitude opposite the arrow in the other small
window.
You E6B manual will have an example you can follow through.
Do you have any advice for the private pilot written
exam?
My number one study suggestion is to go through the study and reference
guide
document and make sure you know something about every listed point. I
guarantee
you that when you get out of the exam, saying, "what was up with the
question
on ....?" when you look it up in the study guide it will be listed, and
when
you look it up in From the Ground Up the explanation there will
be
almost word for word with the correct answer choice.
Native English speakers rarely fail Air Law. You can get tripped up by
a
few tricky questions, but there's no reason you can't get 100% on air
law.
After all, they tell you in advance all the sections of the CARs for
which
you are responsible, and most of them you've already studied for the
PSTAR.
General is hard to get 100% on because it draws from so many areas, but
people
don't fail it often, either.
Met is the big area for failure, and that's because the Met questions
ask
you to put together what you know. When you get to a met question that
seems
impenenetrable, don't guess: you should have the tools to solve it. Be
very
careful about AGL and ASL heights, and read all the notes on the GFAs.
The
questions that seem totally off the way, asking you what the wind will
be
doing at a particular place are often asking about the progress of
fronts.
Once you recognize that the weather materials you have represent a cold
front,
just pull out of your brain every fact about cold fronts that you have
memorized,
and you should be able to figure it out. Sometimes they ask you to use
common
sense, too. I remember a question that had a cold front moving through
an
area in the morning, and they wanted you to tell them about the
behaviour
of the temperature over the next few hours. You needed to take into
account
the fact that it was noon, with clear skies, and so the sun would heat
up
the ground!
The usual reason someone fails Navigation is if they make one mistake
at the
beginning that carries through the whole section. They have been
changing
the exam slightly so that one mistake doesn't affect EVERY question,
too.
Do Nav last, because it's time consuming and if you get bogged down on
it
you will lose easy marks from other sections. Don't complete the entire
nav
log for the nav exercise: do only the calculations required to answer
the
questions. And if the nav log page they give you is confusingly
different
than the one you use at school, don't use it at all: just recreate what
you
are used to on scrap paper. Oh and on the VOR questions, redraw the
airplane
so it is facing in the direction selected on the OBS. They deliberately
draw
the airplanes in the most confusing orientations.
Speaking of scrap paper, they give you two sheets. If you want more you
can
bring back the used sheets and trade for more.
The Transport Canada questions are tricky, but people who take the exam
seriously
usually pass.
BTW, you will see on the net people bragging about getting 98 or 100 on
the
PPL written exam. These people are Americans, and all the questions for
their
exams are available in advance, like for our PSTAR, so of course they
can
get high nineties. Anything over 90 percent is excellent in Canada, and
over
80 percent is still very good.
What are the new
computerized
exams like?
Transport Canada is just switching to computer-administered
examinations.
They are the same exams, just presented on a computer screen instead of
on
paper, and you answer by clicking on the correct answer choice with the
mouse.
For some reason there is slightly more tendency to guess when you're at
a
computer, so guard against that. Look at the question, do any
calculations
necessary to determine the right answer, then look at the choices and
carefully
select the one that match.
The exam timing doesn't start until you click Start, so once you are in
the
exam room, take some time to get settled, look through the charts and
graphs,
and read the instructions. The computer shows you one question at a
time.
You can go backwards and forwards through the exam or jump to any
question.
You can change your answers as often as you like, and you can also
change
back and forth between French and English. At the bottom of the screen,
a
green progress bar shows you how many questions you have answered and a
red
progress bar tells you how much of your time has passed. You can see at
a
glance if you are ahead or behind time, or you can choose to hide the
progress
bar. You also have the opportunity to "bookmark" questions, just as you
might
have put a mark next to one on the old paper form. When you finish the
last
question, a box comes up showing you if you skipped any questions, and
you
can click to go directly to those questions.
When you have completed all the questions, you can tell the computer to
mark
your exam. It will tell you if you still have time left, and give you
the
opportunity to spend more time checking your answers, or you can
confirm that
you are done. Your results will be given to you by the clerk, not
displayed
on the computer.
The computer screen at the exam centre where I tried it was
well-positioned
and easy to read, and I thought the software was well-designed. I
was
initially skeptical about the new system, but now having tried it, I
have
no complaints. You can download
a preview of the exam software from Transport Canada.
Why does the METAR have two different parts telling me
about
the clouds?
The BODY of the METAR, that is the SCT030 BKN050 stuff, tells you the
cumulative
coverage from the ground, to that altitude. The REMARKS, that is the
part
that looks like ST5SC3CI2, gives you the actual coverage at each layer.
It
is independent, not redundant information.
You have to compare the body of the METAR with the ST5SC3. Just by
knowing
that it's ST5SC3 does not tell me whether the sky is overcast or broken
by
the second cloud layer. It depends how they line up. So I have to look
and
see whether it says BKN030, BKN050 or BKN030 OVC050.
Will flying void my life insurance?
The fine print in many policies forbids scuba diving, auto racing and
other
specifically named dangerous sports. I think the term is "named perils."
I know that pilots can buy life insurance. I continued to hold life
insurance
through my former employer, during my own flight training. I had to
answer
a questionnaire about my qualifications and the type of flying I did,
but
it didn't affect my coverage at all.
Every airplane that flies in Canada must have a certain amount of
insurance
per seat, and your school will take care of that, assuming you are
flying
a school airplane. The proof of insurance is one of the documents you
must
carry on board. Some people, especially Americans, carry extra
"renter's
insurance" to cover discrepancies between the rental company's policy
and
the costs actually associated with being stranded somewhere with an
unserviceable
aircraft. Your school may also charge you an insurance surcharge,
because
of the phenomenal rise in insurance costs lately, and they may give you
the
opportunity to pay or waive an extra fee that would reduce the
deductible
in case you damaged the school airplane while flying solo. This
paragraph
is all about the insurance on the airplane, not on you; it's the
airplane
equivalent of car insurance.
Some commercial pilots carry "loss-of-licence" insurance, that would
help
them out if they lost their medical.
If your own policy -- haul it out of the file folder and scan the fine
print
-- doesn't specifically forbid private aviation, you should be okay.
Even
if it does you may be okay. Mine did, so I called and asked, filled in
the
form I mentioned, and they were happy. Definitely check out the effect
flying
would have on your policy.
The last thing I'll mention is that when a student's spouse or parent
has
a concern like that, I like to pause and ensure that they don't have an
exaggerated
concept of the danger of aviation. If the student's family thinks that
flying
is crazy-dangerous, I try to get them to come into the school, to learn
about
the safety precautions, and maybe to go for a flight so that they get a
better
idea of what is involved.
Can
Americans
fly into Canada with an FAA licence?
Yes. The general rule is that the nationality of your licence must
match
the registration of your airplane. If you have an FAA licence you may
fly
an N-registered airplane in Canada, but you must fly according to
Canadian
laws, so be sure to do your homework. The PSTAR
section of this site (read the commentaries) gives basic Canadian
air
law, and I have a glossary
for US-Canada terminology. Americans may also be disconcerted by
the
lower level of ATC services in Canada. Radar vectors and VORs are
available
only in the densely populated south. Make sure you can navigate on your
own!
I plan a page on "flying in Canada for Americans" later.
Can I fly a Canadian airplane on
my
foreign pilot licence?
No. If you want to rent a Canadian registered airplane, you can either
obtain
a foreign licence validation or a Canadian pilot licence. The licence
validation
is sufficient for tourists. If you become a resident of Canada, you
will
need a full pilot licence.
How do I receive a foreign
licence
validation?
To receive a licence validation certificate, you must go to a Transport Canada office
and bring your foreign licence, other identification, a Canadian medical certificate, proof that you
have
both fulfilled the flight
time requirements of the Canadian private licence and have
completed
five takeoffs and landings in the last six months, and the licensing
fee. Proof of the flight requirements should consist of your
logbook,
and charts or other means of showing that you have completed a 150 nm
cross
country trip. You will then be required to write the PSTAR
test
of Canadian air regulations, and earn a mark of at least 90 percent. If
all
your paperwork is in order you should receive your licence validation
certificate
the same day.
In case anything has changed since I wrote this, read the letter of the
law
in CARS
Standard 421.
How do I convert my foreign
licence
to a full Canadian one?
Do everything required for the licence validation certificate, plus
write
the PPAER (private pilot written exam) and take the private pilot
flight
test.
Can I learn to fly in Canada if I
am
neither a citizen nor a resident?
Yes. A visitor can train in Canada and receive a Canadian private
licence.
Hundreds do every year, from countries all over the world, as we have
low
costs and high quality training. Once you earn a Canadian licence, it
entitles
you to fly Canadian registered airplanes in any country in the world.
Can I transfer training time from
another
country to Canada?
Yes. The training time you already have in another ICAO country is
transferrable
to Canada. (This rule came into effect March 2003, so if your flying
school
doesn't know it, show them CAR
421.26 (9), and don't forget who saved you all that time and
money).
To ensure that your foreign training is accepted by Transport Canada,
bring
a letter (in French or English) from your foreign flight instructor
listing
the exercises (taxiing, take-off, stalls, slow flight, steep turns,
etcetera)
that you have covered, and also bring a photocopy of your instructor's
licence,
to prove that he or she is a real flight instructor. This won't
necessarily
be required, but it could be.
Help me plan a trip by air in British Columbia
BC is spectacular for flying. I'm not sure how many hours per day you
plan,
but if someone said "I have a week, take me flying in BC," I'd do
something
like this:
From Chilliwack (CYCW) climb up to 10,000' and fly around Mt Baker, a
picture
perfect active volcano that will likely sill have snow on it in August.
From there, fly over the Gulf Islands in the Georgia Staight to
Victoria
(CYYJ) where you can eat a good lunch at the Spitfire Grill, right on
the
airport, just ask the ground controller for taxi instructions. It's a
short
flight to Tofino (CYAZ). There is camping immdiately next to the
airport
at Tofino, and a spectacular beach a short walk away. Bella Bella
(CAF2)
is about 3 hours north of there, a rugged area, that not a lot of
British
Columbians have ever seen. If you continue up to Sandspit, you're in
the
Queen Charlotte Islands, or Haida Gwai. This is spectacular wilderness,
many of the locals are native Indians, and there is a resurgence of
native
culture.
You can't go much further north without reaching Alaska, so turn east
and
fly the valley Terrace, Smithers, to Prince George. There's not a lot
other
than avgas to recommend these towns as places to stop, but the scenery
is
breathtaking mountains. From Prince George I love the valley route
right
along the continental divide via Valemount and Blue River. From there
you
can cross the divide to Calgary, or stay in BC and come out in the
Okanagan,
with wonderful fruit -- and award-wining wine, if you want to take a
day off
flying. Salmon Arm, Vernon, Kelowna, Penticton are all airports with
reasonable
access to communities on lakes, with swimming and fishing and summer
fun.
If you like the wild west, you could detour north again and probably
find
yourself some horseback riding in ranching country in the Cariboo,
around
Williams Lake and 100 Mile House. And you should land in Quesnel and
say
hi to Sven at Quantum Air,
because
he is a nice guy.
Some more spectacular valleys include the route from Lillooet, Seton
Portage,
Whistler to Squamish. That brings you out at Horshshoe Bay, right near
Vancouver.
You can easily get clearance to orbit over the downtown, by day or
night.
Much of this is really rugged daytime-only flying. Check ahead
carefully
for fuel availability, and be prepared for weather delays, mountain
turbulence,
and high density altitudes.
Please respect published overflight rules for national parks, and stay
at
least 2000' overhead wildlife, or higher if your airplane noise seems
to
disturb them at all.
Try these sites for British Columbia tourist information.
http://www.hellobc.com/
http://www.nbctourism.com/
http://www.britishcolumbia.com/
Can I fly in the United States with my Canadian licence
You can fly a Canadian registered airplane anywhere in the world with a
Canadian
licence. If you want to fly an American N-registered airplane, you need
an
FAA permit. Take your Canadian licence and medical to a Flight Standards
District
Office (FSDO) in the United States, and the folks there will issue
you
an FAA permit "on the basis of" your Canadian licence. It is a good
idea to
make an advance appointment with the FSDO.
Other countries have similar visitor's permits.
There is an incorrect answer in
your
PSTAR Guide.
Is it in MINE or in your school's answer key? It could be either.
Please ask.
Transport Canada doesn't send your school a PSTAR or an answer guide.
Your
school is responsible for making up a PSTAR by selecting from the
available
questions, and for providing the answer key. Flight instructors make
mistakes
too, especially as some of the questions are really hairsplitting.
For example, question 3.03 is sometimes marked with #1 correct and
sometimes
#2. Lets look at it.
Answer choice one says you can leave out ANY letters, if air traffic
services
does first, while choice two says you can omit the FIRST TWO, if air
traffic
services does. So the only difference between one and two is the number
of
letters ATS can omit.
The PSTAR references list says AIP COM 5.7.1, but there is no 5.7.1:
Transport
didn't update the reference when they updated the AIP. The correct
reference
is AIP COM 5.8.1, which states "Subsequent communications may be
abbreviated
to the last three letters if this abbreviation is initiated by
ATS."
Seeing as there are always five letters (including the C-), using the
last
three letters is exactly the same as omitting the first two letters. So
choice
#2 is definitely the best answer, right in line with the reference.
There's nothing actually wrong with answer choice one, because ATS
won't omit
more than the first two letters anyway, but this is a typical Transport
Canada
question.
Please let me know of any apparent errors on school-marked -- or my --
PSTAR.
Does CARs 605.33 (1) make any sense to anyone?
Yes. CARs
605.33 (1) made sense when it was written because they were phasing
in
rules for flight data recorders. It could safely be rewritten now to
read:
(1) Subject to Section 605.34, no
person
shall conduct a take-off in any of the following aircraft unless the
aircraft
is equipped with a flight data recorder that conforms to the Aircraft
Equipment
and Maintenance Standards:
a) any multi-engined turbine-powered aeroplane operated under Subpart 5
of
Part VII; and
b) any other multi-engined turbine-powered aircraft that has a
passenger
seating configuration, excluding any pilot seats, of 10 or more and
that
was manufactured after October 11, 1991.
The references to two dates in 1997, the mention of pressurization, and
the
reference to part 704, are all irrelevant now that the implementation
date
for each phase of the rule has passed. While its vaguely
interesting
to note that part 704 pressurized multi turbine airplanes over 5700 kg
required
FDRs at an earlier date than other multi-turbines, it doesn't have
anything
to do with the current rules.
The bit about October 11, 1991 is probably to do with the difficulty of
retrofitting
FDRs to older aircraft, so thay decided that only 705 operations had to
bear
that burden.
Can you explain the effect of aircraft weight on gust
load?
This whole gust load thing is very interesting. Why does the safe
speed
to fly in gusts DECREASE as the airplane gets lighter?
Remember the equation of lift: Lift = 1/2 CL * p * S * v2
Where CL is the coefficient
of lift,
dependent on wing form and angle of attack
p
is air
density
S
is wing
area
v
is airspeed,
and the little two means that it is squared (multiplied by itself)
You don't have to know the whole equation, just remember that lift
increases
if the airplane goes faster, or if the angle of attack increases.
Remember also that when the angle of attack reaches the stalling angle,
lift
decreases. The airplane can stall at any speed, if that stalling angle
is
reached. The stall speed quoted in a small airplane POH represents the
unaccelerated
power off stall speed at gross weight. If you slow down gradually, you
have
to increase the angle of attack to maintain lift. At gross weight you
will
reach that angle of attack at the published stall speed. At a lower
weight,
you will not stall until you reach a lower speed, because you need less
lift
to counteract your weight. Your stall speed decreases with the
square root
of the weight.
But, if gusts or abrupt control deflections increase the angle of
attack abrubtly,
you can reach the stalling angle of attack at any speed. The more
abrupt
the increase, the higher the stall speed. As just discussed, the
increase
in angle of attack increases lift. For any configuration, we can divide
the
lift by the weight to find a number we call the load factor. If lift is
double
the weight, you have a load factor of 2, also referred to as a 2 G
force
on the airplane. That load factor, or G-force is a measurement of how
abrubtly
the airplane has been manoevered. Your POH will state the maximum loads
your
airplane is designed to handle in load factor. A typical airplane can
handle
a load factor of +3.8. Your stall speed increases with the square
root
of the load factor.
Lets say your airplane has a gross weight of 5000 lbs, a stall
speed
of 70 kts, and a maximum load factor of +3.8 Gs. That means
its
wings can withstand a weight of
3.8 x 5000 = 19000 lbs.
Suppose the airplane's engine weighs 400 lbs. So the engine
mounts,
holding the engine on, are designed to hold
3.8 x 400 = 1520
lbs. And so on, for the baggage compartment floor, the pilot seat
rails,
the hinges in the rudder, and all those parts you'd like to keep
attached
to your airplane.
You're flying at gross weight in level flight, at 130 kts. The
wings
feel 5000 lbs. 5000/5000 = 1. You feel 1 G.
The
engine mounts feel 400 lbs. Everything is good.
A gust suddenly increases the angle of attack. More lift is generated.
The
wings are now feeling 17000 lbs of force.
17000/5000 = 3.4
Gs. You feel slammed into your seat by the sudden turbulence. You
haven't
exceeded the allowable load, you're okay.
The turbulence gets even worse, the force on the wings increases ... if
it
increases anymore you'll reach your limit of 19000 lbs. But wait,
what's
your stall speed? At 3.6 Gs, the stalling speed is
70 x sqrt(3.6) = 133 kts.
You are below your stalling speed. The airplane stalls
momentarily,
the excessive force is never generated, and you're on your way.
Good
thing you weren't going 140 kts!
Now you're on your way home, minimum fuel, no passengers, empty, at
just
3000 lbs. But you are still flying 130. You hit that same
turbulence.
Same wing, same speed, same 17000 lbs force is generated. Your
wings
can take it. But you have a lighter airplane, so the load factor is
greater:
17000/3000 = 5.7 Gs! Can the engine mounts take it? Can the
hinges
in your elevator? But what about stalling? Won't the airplane stall
before
it takes that very high load? What's your stalling speed? It decreases
with the square root of your weight, which takes it
down
to about 55 kts for this very light load. So at 5 Gs:
55 x sqrt(5) =
123. You're still above your stall speed at 5 Gs! Stall speed
becomes
irrelevant as your airplane breaks up.
If you had been flying at 100 kts and 3000 lbs, what would
have
happened in that gust?
Your stall speed at 3.8 Gs would be
55 x sqrt(3.8) = 107 kts.
You would have stalled BEFORE dangerous loads developed on the airplane.
The manufacturer specifies a manoevering speed, called Va, defined as
the
maximum speed at which full abrupt control deflections will not damage
the
aircraft. Below that speed if you encounter a sudden gust load, or try
a
high G manoever, you will stall the aircraft, not break it. In
turbulence,
fly the published Va for your airplane, but decrease Va as the
square
root of your weight decreases.
Why can't I get the hang of landings?
Don't worry about the landings. Almost everyone feels they aren't
getting
it at first, but eventually it clicks.
1. Work on the approach just as hard as the landing. Make sure you get
to
the beginning of the runway at the right speed and altitude, and
properly
TRIMMED. If you're not trimmed, speed control is difficult, so it is
difficult
to be consistent, and then the flare becomes more difficult. Remember
to
use POWER for altitude, PITCH for speed and RUDDER for direction.
2. Pay particular attention to where your flight instructor tells you
to
LOOK, and look in the same place while your instructor is landing as
when
you land, so you get the whole picture.
3. When you think the airplane is just about to land, pull back a tiny
bit
more. Pilots don't land airplanes, airplanes land themselves. Your job
is
to keep it from crashing until it runs out of speed and has to land.
The
slower the airplane is going, the more you have to pull to get the same
change
in pitch.
Remember that you are in slow flight during the flare, and your goal is
to
stall the airplane right over the runway. That's why your instructor
had
you practise aircraft control in slow flight and in the stall.
Be patient with yourself and with the airplane. Eventually you will get
it.
It's not on your site, but could you tell me ..?
I love answering questions. Go on, ask.
Back to Top | Robyn's Flying Start Home | E-mail Robyn and ask her a question
This page written 22 May 2003 by Robyn Stewart. Last updated 15
February
2004.
Copyright 2003 Flying
Start
Intiatiatives.
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