ATPL General Navigation - Class 6: Distance.
Summary
TLDRIn this informative aviation class, Grant explains the various units used to measure distances in the field. He clarifies the use of nautical miles for long distances, converting them to meters, kilometers, and feet, and highlights the 1852 meters equivalence of a nautical mile. The video also touches on the use of statute miles in the United States and the conversion between different units. Grant simplifies the concept with practical examples, such as runway dimensions and ILS approach diagrams, and shares a helpful trick for descent planning based on a three-degree slope, which equates to a thousand feet every three nautical miles.
Takeaways
- 🌐 Units in aviation for measuring distance can be confusing due to the variety used, but they are specific to the context, such as altitude in Europe often being measured in feet.
- 🚀 Long distances are typically measured in nautical miles, which are based on a minute change in latitude and equate to 1852 meters or 1.852 kilometers.
- 📏 The conversion between nautical miles and feet is 60.76 feet per nautical mile, and one meter equals 3.28 feet for conversions between meters and feet.
- 🔢 To convert nautical miles to kilometers, multiply the nautical miles by 1.852, and to convert to feet, multiply by 60.76 and then by 3.28.
- 🇺🇸 In the United States, the statute mile is also used for measuring distance, with one statute mile equaling 1.609 kilometers or 1609 meters.
- 📐 For short distances, measurements are generally in feet or meters, and the conversion between them is straightforward using the 1 meter to 3.28 feet ratio.
- ✈️ Runway dimensions and vertical heights, such as threshold elevation, are often given in feet for aviation purposes.
- 📊 The side view of an ILS approach illustrates the use of feet for vertical distances, with a common slope of three degrees equating to a descent of 1000 feet every three nautical miles.
- 🌁 Aviation visibility minima are given in both feet and meters/kilometers, indicating the required cloud base and visibility for different types of approaches.
- 📉 The three-degree slope trick is a helpful tool for descent planning in aircraft, simplifying the math for pilots when descending towards an airport.
- 📝 While the three-degree slope trick might not be on exams, it's a practical tip for pilots to ensure they are on the correct vertical path for landing.
Q & A
What is the main topic of the video class presented by Grant?
-The main topic of the video class is the range of units used in aviation to describe various distances, with a focus on conversions between different units.
Why are specific units used for specific measurements in aviation?
-Specific units are used for specific measurements in aviation to ensure accuracy and standardization in describing distances, which is crucial for safety and efficiency in flight operations.
What is the definition of a nautical mile according to the video?
-A nautical mile is defined as one minute change in latitude and is equivalent to 1852 meters or 1.852 kilometers, and also equals 6076 feet.
How can you convert nautical miles to kilometers?
-To convert nautical miles to kilometers, you multiply the number of nautical miles by 1.852, since one nautical mile is equal to 1.852 kilometers.
What is the conversion factor between meters and feet?
-The conversion factor between meters and feet is that one meter equals 3.28 feet.
Can you provide an example of converting five nautical miles to kilometers and feet as shown in the video?
-Yes, five nautical miles times 1.852 equals 9.26 kilometers. To convert to feet, you would multiply 9260 meters by 3.28 to get 30,372.8 feet.
What is a statute mile and how does it differ from a nautical mile?
-A statute mile is a unit of distance used in the United States and is equal to 1.609 kilometers or 1609 meters. It differs from a nautical mile, which is longer and used primarily in aviation and marine navigation.
How are short distances typically measured in aviation?
-Short distances in aviation are generally measured in feet or meters, using the conversion factor between the two as needed.
What is the significance of the three-degree slope in instrument approaches as mentioned in the video?
-The three-degree slope is significant because it simplifies the mathematical calculations for pilots during flight, allowing them to estimate their descent profile easily. For every three nautical miles, the altitude should decrease by approximately one thousand feet.
Can you provide an example of how the three-degree slope is used for descent planning in the video?
-In the video, it is explained that if a plane is at 35,000 feet and needs to descend to 2,000 feet, with a three-degree slope, they would need to start descending 99 nautical miles before the runway threshold to achieve a gentle slope towards landing.
What are the units used for measuring visibility and cloud base in the minima for instrument approaches shown in the video?
-The units used for measuring visibility and cloud base in the minima for instrument approaches are feet for altitude and a combination of meters/kilometers for visibility.
Outlines
📏 Units of Distance in Aviation
In this segment, the instructor, Grant, introduces the topic of various units used to measure distances in aviation. He emphasizes the importance of understanding these units, especially since different regions may use different standards. The primary focus is on the conversion between nautical miles, feet, and meters. The instructor explains that in Europe, altitude is typically measured in feet. He provides a detailed example of converting five nautical miles into kilometers and feet, illustrating the process with mathematical calculations. Additionally, he touches on the use of statute miles in the United States and offers a conversion factor for nautical miles to statute miles. The segment aims to clarify the confusion surrounding these units and their conversions.
📐 Aviation Distance Conversions and Approach Slopes
This paragraph delves deeper into the specifics of vertical distance measurements in aviation, predominantly using feet. The instructor discusses the side view of an ILS (Instrument Landing System) approach, highlighting the importance of vertical distances in feet, such as the threshold elevation and the descent path. He introduces the concept of a 3-degree glide slope, which is a common angle for instrument approaches, facilitating easy calculations for pilots in flight. The instructor provides a practical example of descent planning using the 3-degree slope rule, explaining how to estimate the distance and altitude for a proper approach. He also mentions visibility minima requirements during approaches, given in both feet and meters/kilometers. The summary concludes with a set of key conversion factors: one nautical mile equals 1,852 meters or 6,076 feet, one statute mile equals 1.609 kilometers, and one meter equals 3.28 feet, encouraging students to memorize these for ease of conversion.
Mindmap
Keywords
💡Nautical Mile
💡Altitude
💡Conversion
💡Statute Mile
💡Runway Dimensions
💡Vertical Distance
💡Instrument Approach
💡Visibility
💡Cloud Base
💡Descent Planning
Highlights
Introduction to the range of units used in aviation for measuring distances.
Specific units are used for measuring different things in aviation.
In Europe, altitude is measured in feet.
Exploration of conversions between different units of distance.
Long distances are typically measured in nautical miles.
A nautical mile is defined as one minute change in latitude.
Conversion rates: 1 nautical mile equals 1852 meters or 1.852 kilometers.
Conversion rates: 1 nautical mile equals 6076 feet.
Conversion between feet and meters using 1 meter equals 3.28 feet.
Example calculation: converting 5 nautical miles to kilometers and feet.
Statute miles are used in the United States for distance measurements.
Conversion: 1 statute mile equals 1.609 kilometers or 1609 meters.
Recommendation to remember a few key conversions for practical use.
Short distances are measured in feet or meters.
Example of runway dimensions given in meters.
Vertical heights are generally discussed in feet.
Illustration of vertical distances in an ILS approach diagram.
The 3-degree slope rule for instrument approaches simplifies calculations.
Practical application of the 3-degree slope for descent planning.
Summary of key conversions: 1 nautical mile, 1 statute mile, and 1 meter.
Transcripts
i would walk 500 miles and i would walk
800 kilometers more just to be the man
who walked 870 nautical miles to fall
down at your door
i'll do that that's funny
[Music]
hi i'm grant and welcome to the sixth
class in the genome series today we're
going to be taking a look at the range
of units we use in aviation to describe
various distances
can be a bit confusing at first because
there are so many but generally specific
things are measured in specific
distances for example in europe we use
feet for altitude so this class is going
to be fairly short but it's basically
going to look at the conversions between
different units that are used for
measuring distance
as i said in the intro usually specific
things are measured in very specific
units so let's start with long distance
which is normally measured in nautical
miles
we established in the second class when
we looked at latitude and longitude
that a nautical mile is
one minute change in latitude
normally we don't think of distances as
degrees of latitude though so let's put
some numbers to it
one nautical mile
is 1852
meters
or 1.852 kilometers
and it also equals
60
76
feet
and we can convert between feet and
meters
using the conversion of one meter
equals 3.28
feet so let's just check
our conversions to see if they work i'm
going to pick i don't know five nautical
miles and i want the value in
kilometers and feet so
five
nautical miles
times by
one point eight five two because it's
185
uh
1850 meters or 1.852 kilometers and that
equals and that equals
9.26
kilometers
and then if we want to find the value in
feet
we would just use this conversion here
and it would be
9260
meters times by
3.28 to get into feet which gives us 30
372.8
feet and if we were then to divide this
number
by 60
076 feet we should get back to five
knock miles so let's just do that so we
have 30
372
divided by
60
76
equals
4.99 yeah let's call that five
so occasionally
in the states like the united states i
think they also use the statute mile for
distance
and if you need to then the conversion
for that
that is good to remember is one statute
mile
equals 1.609
kilometers or
1609
meters
you could also remember that there's a
conversion between knock miles and
statute miles but i would recommend just
remembering a few conversions so you get
to a common point and then convert from
there
and what i mean by that is
say i wanted those five nautical miles
from earlier
in
statute miles
i have one conversion in my head for
nautical miles which is 1852 meters well
i have two or 60 76 feet
i can convert it into meters
and then
know what that is in kilometers and i
can go back into statute miles
i already know that 3.28 feet are in a
meter and that 1.609 kilometers are in
statute mile in
every statute mile
so i can get to a statute mile by going
through meters and kilometers
if you find it easier just to remember
that
one statute mile
to one knock mile whatever that
conversion is then go for it but that's
just my personal recommendation
short distances are generally measured
in feet or meters
and using that same conversion that
we've seen before you can get between
the two
so
this is just an example of a chart into
a place called pharaoh which is in the
south of portugal that we go to often
and
this diagram here is runway dimensions
which are in meters
so you can see that it's
2445 meters long by 45 meters wide
and
when we're talking about vertical
heights we generally talk about feet
and the threshold elevation is 24 feet
and you can also see some
more examples of vertical distances
being measured in feet
so this
is the
side view of an ils approach coming in
and you can see that it starts at 2000
feet comes along and then at
six nautical miles because we're talking
horizontal distances
we start to go down and at four nautical
miles we've got to be 1350 feet
and then we keep going down
and then we get all the way to the
threshold elevation
which is at 24 feet
and that would be our zero nautical mile
mark
for
the ils
you can also see some more examples down
here these are our minima that we use
we've got to have at least these
categories of visibility
so you can see it's feet and then it's
in meters slash kilometers and then the
other one is in feet it gives you the
units here
so we need
a
cloud base this is
um of 200 feet that means the lowest
level of cloud essentially
and then we need at least 750 meters of
visibility or if you're doing this
slightly different type of approach you
need 310 cloud base and one kilometer
visibility and then this is our altitude
that we would descend down to before
deciding whether to
go around you can also see something
interesting about the vertical heights
on this kind of diagram
you can see that the
slope here
says three degrees three degrees is a
very common slope for
instrument approaches
and the reason behind it is because it
makes the maths quite easy
for us when we're in the air
you can see that as we go out to
six nautical miles it's 2000 feet
so or we could say that every three
knock miles it's a thousand feet it's
not exact but it is
pretty good estimation
so you can say that at roughly
three nautical miles to go we should be
a thousand feet
at six nautical miles we should be 2000
feet you can project it all the way back
up and you could say that for us to be
on profile as they call it like on the
correct sort of vertical path
and we're at
12
nautical miles away from the runway
we should be about 4 000 feet for it to
make sense so this is what we can use
for our like descent planning as well
that that three degrees
uh slope
every three nautical miles is a thousand
feet
we basically use that to plan when we're
going to start our descent from our
cruising altitude so say this was our
airport up faro
and we are at
we know we need to get down to that what
was it two thousand feet
it was two 000 feet here
and we're at
35 000 feet
we know that we have to change in height
by
33 000 feet and with a nice gentle slope
of three degrees which is roughly a
thousand feet for every three nautical
miles
for us to descend this thirty three
thousand feet we'll need three nautical
miles for every thousand feet of that we
would just multiply that by three and we
would find out that we needed to send
99 nautical miles before this point
and that point if you remember was at
six nautical miles
so if we
descend 105 nautical miles before the
runway threshold of faro
we should get a nice gentle slope in
towards landing
that won't come up in the hbl exams but
it's just a handy trick to know when
you're actually flying aircraft so as i
said nice short class there the only
real things to remember are these
conversions and that three degree
uh slope trick of
1000 feet is three nautical miles
although that won't come up in the exam
i don't think
so one nautical mile 180
1852 meters or 60 76 feet
one statute mile is 1.609 kilometers or
1 609
one meter is 3.28 feet
and convert between them as you see fit
[Music]
5.0 / 5 (0 votes)