R172K Approach Configuration

Anyone give me a clue of the approach configuration of R172K? For
instance, now I use 100kts, 15inch, 2500RPM with no flaps for the
precision approach (ILS) for the training but it is not stable and too
fast for landing after DA.

I insist 90kts is good speed for the approach level and the precision
approach for R172K but my instructor suggested 100kts in terms of some
reason like the strong wind of winter.

I would appreciate if someone could show me the power setting of
approach configuration like non-precsion, precision, approach level for
R172K. Thank you.

facpi wrote:
Anyone give me a clue of the approach configuration of R172K? For
instance, now I use 100kts, 15inch, 2500RPM with no flaps for the
precision approach (ILS) for the training but it is not stable and too
fast for landing after DA.

I insist 90kts is good speed for the approach level and the precision
approach for R172K but my instructor suggested 100kts in terms of some
reason like the strong wind of winter.

I would appreciate if someone could show me the power setting of
approach configuration like non-precsion, precision, approach level
for
R172K. Thank you.

I like the recommendations made in Peter Dogan's book, The Instrument
Flight Training Manual. However, as your instructor said, there is no
single right power setting. If you assume no wind conditions, then a
90K approach speed works well as that yields close to 90 knots ground
speed (not exact due to the descent angle, but really close) which
matches up with one entry in the time charts for timed approaches.

However, given that you typically have at least some headwind, and more
in general in the winter as your instructor stated, if you figure a
nominal 10K headwind, then approaching at 100K airspeed again yields a
ground speed close to 90K which again makes it easy to pull the time
from the approach plate for approaches that are timed. And if you can't
land a 172 from 100K at a typical 200' ILS DH, then you need much more
practice.

It isn't unusual at larger airports to be asked to keep your speed up
for following traffic. I typically fly the ILS at 100K in the Arrow
that I fly, but I recently flew one at 140K due to a following RJ. It
really wasn't a big deal. I chopped the power at DH and had no problem
making a normal landing. Once you get "normal" approaches well in hand,
you want to go up and practice approaches at higher airspeeds so they
become familiar also.

This is the only area where I disagree a little with Dogan as he does
come across a little as suggesting that you can fill a card with 5 or 6
aircraft configurations and be happy ever after. The real world isn't
that simple. My primary instructor was an old-time seat of the pants
insructor as opposed to the more modern "by the numbers" philosophy.
Personally, I think both have their place. I use Dogan's by the numbers
approach to get a starting point, but then use whatever adjustments are
required to get the performance I need in the prevailing conditions.
This is more of a trial and error process although with more experience
you will get to the desired configuration more quickly.


Matt

Matt Whiting wrote:

I like the recommendations made in Peter Dogan's book, The Instrument
Flight Training Manual. However, as your instructor said, there is no
single right power setting. If you assume no wind conditions, then a
90K approach speed works well as that yields close to 90 knots ground
speed (not exact due to the descent angle, but really close) which
matches up with one entry in the time charts for timed approaches.


Don't forget that 90 K indicated airspeed only equals 90 knots ground speed at sea level on a standard
day with no wind. At higher altitudes, your TAS (and GS depending on the wind) will be significantly
higher.

Regardless, I agree with most of your post. I find the Dogan-style performance numbers are a good
starting point, and help to get configuration changes stabilized. It does then require tweaking to suit the
specific conditions, though.

Mike

-----Original Message-----
From: facpi ]
Posted At: Monday, January 01, 2007 7:55 AM
Posted To: rec.aviation.ifr
Conversation: R172K Approach Configuration
Subject: R172K Approach Configuration


Anyone give me a clue of the approach configuration of R172K? For
instance, now I use 100kts, 15inch, 2500RPM with no flaps for the
precision approach (ILS) for the training but it is not stable and too
fast for landing after DA.

I insist 90kts is good speed for the approach level and the precision
approach for R172K but my instructor suggested 100kts in terms of some
reason like the strong wind of winter.

I would appreciate if someone could show me the power setting of
approach configuration like non-precsion, precision, approach level
for
R172K. Thank you.




--
facpi

For now follow your instructor's direction; after all he or she is the
one you chose to prepare you for your checkride. The 172 is plenty
stable at 100K and there is rarely a reason that you can't make a no
flap landing after an approach.

One reason a lot of instructors use the higher speeds is it forces you
to deal with things more rapidly. You won't be surprised when asked to
"keep your speed up on the localizer" as you work at larger (air
carrier) airports. When I worked out of Seattle years ago, we used to
take students down to Portland on short trips to get them familiar with
dealing with the whole enroute structure. Portland needed best possible
speed down the localizer because they were only using one runway.
Approach asked one of my students what his speed down final would be as
we entered the hold over the IAF. Even though I had pre-briefed to use
120 to 130K down final, my student told them he'd give them 90K (we were
in a Commander 112A). After two trips around the hold, approach asked
him again what his speed down final would be. I suggested that he ask
them what they needed, to which approach responded "125K if possible".
He agreed to 125K and we were cleared for the approach almost
immediately.

Another benefit of the higher speed is the aircraft is more responsive
to corrections and less affected by crosswinds (smaller wind correction
angles needed).

Yet another benefit (students may see it as a burden however) is that
your reactions have to be more precise and you can't sit around to see
what happens. You have to think farther out in front of the aircraft
when you are moving faster.

Finally, if you are flying into fields that need you to use higher
speeds for traffic sequencing you are going to be landing at airports
that have runways long enough to accommodate most light aircraft even if
they have to bleed of 30 or 40 knots after breaking out. So you land
long and make a mid-field turnoff - no big deal.

10 knots (the difference between 100 and 90) may not seem like a lot
now, but it forces you to deal with lots of other issues that will
eventually arise when you start working in the system. In all
probability though, your instructor will most likely start you flying
the approach at different speeds so you can experience the different
timings, responsiveness, sounds, and aircraft attitudes that go along
with them -- that usually comes later in the syllabus though. We would
teach approaches from 80K up to 140K just to expose the students to what
might be expected in the real world.

-----Original Message-----
From: Matt Whiting ]
Posted At: Monday, January 01, 2007 10:36 AM
Posted To: rec.aviation.ifr
Conversation: R172K Approach Configuration
Subject: R172K Approach Configuration

....
This is the only area where I disagree a little with Dogan as he does
come across a little as suggesting that you can fill a card with 5 or
6
aircraft configurations and be happy ever after. The real world isn't
that simple. My primary instructor was an old-time seat of the pants
insructor as opposed to the more modern "by the numbers" philosophy.
Personally, I think both have their place. I use Dogan's by the
numbers
approach to get a starting point, but then use whatever adjustments
are
required to get the performance I need in the prevailing conditions.
....

Matt

Matt makes a very good point in that the "modern by the numbers
philosophy" is a good starting point, and the "old-time seat of the
pants" philosophy will expose you to the real world. Both absolutely
have a place in aviation (or anything else for that matter).

On Mon, 01 Jan 2007 16:35:37 GMT, Matt Whiting
wrote:

facpi wrote:
Anyone give me a clue of the approach configuration of R172K? For
instance, now I use 100kts, 15inch, 2500RPM with no flaps for the
precision approach (ILS) for the training but it is not stable and too
fast for landing after DA.

I insist 90kts is good speed for the approach level and the precision
approach for R172K but my instructor suggested 100kts in terms of some
reason like the strong wind of winter.

I would appreciate if someone could show me the power setting of
approach configuration like non-precsion, precision, approach level
for
R172K. Thank you.

I like the recommendations made in Peter Dogan's book, The Instrument
Flight Training Manual. However, as your instructor said, there is no
single right power setting. If you assume no wind conditions, then a
90K approach speed works well as that yields close to 90 knots ground
speed (not exact due to the descent angle, but really close) which
matches up with one entry in the time charts for timed approaches.

However, given that you typically have at least some headwind, and more
in general in the winter as your instructor stated, if you figure a
nominal 10K headwind, then approaching at 100K airspeed again yields a
ground speed close to 90K which again makes it easy to pull the time
from the approach plate for approaches that are timed. And if you can't
land a 172 from 100K at a typical 200' ILS DH, then you need much more
practice.

It isn't unusual at larger airports to be asked to keep your speed up
for following traffic. I typically fly the ILS at 100K in the Arrow
that I fly, but I recently flew one at 140K due to a following RJ. It
really wasn't a big deal. I chopped the power at DH and had no problem
making a normal landing. Once you get "normal" approaches well in hand,
you want to go up and practice approaches at higher airspeeds so they
become familiar also.

This is the only area where I disagree a little with Dogan as he does
come across a little as suggesting that you can fill a card with 5 or 6
aircraft configurations and be happy ever after. The real world isn't
that simple. My primary instructor was an old-time seat of the pants
insructor as opposed to the more modern "by the numbers" philosophy.
Personally, I think both have their place. I use Dogan's by the numbers
approach to get a starting point, but then use whatever adjustments are
required to get the performance I need in the prevailing conditions.
This is more of a trial and error process although with more experience
you will get to the desired configuration more quickly.


Matt

Would you explain to me how/why you are doing ILS approaches above max
gear extended speed? (140KTS) Your post indicates that you held that
speed to DH.

Mike Adams wrote:
Matt Whiting wrote:


I like the recommendations made in Peter Dogan's book, The Instrument
Flight Training Manual. However, as your instructor said, there is no
single right power setting. If you assume no wind conditions, then a
90K approach speed works well as that yields close to 90 knots ground
speed (not exact due to the descent angle, but really close) which
matches up with one entry in the time charts for timed approaches.



Don't forget that 90 K indicated airspeed only equals 90 knots ground speed at sea level on a standard
day with no wind. At higher altitudes, your TAS (and GS depending on the wind) will be significantly
higher.

Regardless, I agree with most of your post. I find the Dogan-style performance numbers are a good
starting point, and help to get configuration changes stabilized. It does then require tweaking to suit the
specific conditions, though.

Yes, very true. I was trying to keep it simple and most people in the
USA fly from airports that are 2,000' MSL or less which doesn't
introduce huge errors due to non-standard conditions. However,
certainly if you are landing in Leadville, then it is a big deal.

Matt

Bill Zaleski wrote:

On Mon, 01 Jan 2007 16:35:37 GMT, Matt Whiting
wrote:


facpi wrote:

Anyone give me a clue of the approach configuration of R172K? For
instance, now I use 100kts, 15inch, 2500RPM with no flaps for the
precision approach (ILS) for the training but it is not stable and too
fast for landing after DA.

I insist 90kts is good speed for the approach level and the precision
approach for R172K but my instructor suggested 100kts in terms of some
reason like the strong wind of winter.

I would appreciate if someone could show me the power setting of
approach configuration like non-precsion, precision, approach level
for
R172K. Thank you.

I like the recommendations made in Peter Dogan's book, The Instrument
Flight Training Manual. However, as your instructor said, there is no
single right power setting. If you assume no wind conditions, then a
90K approach speed works well as that yields close to 90 knots ground
speed (not exact due to the descent angle, but really close) which
matches up with one entry in the time charts for timed approaches.

However, given that you typically have at least some headwind, and more
in general in the winter as your instructor stated, if you figure a
nominal 10K headwind, then approaching at 100K airspeed again yields a
ground speed close to 90K which again makes it easy to pull the time

from the approach plate for approaches that are timed. And if you can't

land a 172 from 100K at a typical 200' ILS DH, then you need much more
practice.

It isn't unusual at larger airports to be asked to keep your speed up
for following traffic. I typically fly the ILS at 100K in the Arrow
that I fly, but I recently flew one at 140K due to a following RJ. It
really wasn't a big deal. I chopped the power at DH and had no problem
making a normal landing. Once you get "normal" approaches well in hand,
you want to go up and practice approaches at higher airspeeds so they
become familiar also.

This is the only area where I disagree a little with Dogan as he does
come across a little as suggesting that you can fill a card with 5 or 6
aircraft configurations and be happy ever after. The real world isn't
that simple. My primary instructor was an old-time seat of the pants
insructor as opposed to the more modern "by the numbers" philosophy.
Personally, I think both have their place. I use Dogan's by the numbers
approach to get a starting point, but then use whatever adjustments are
required to get the performance I need in the prevailing conditions.
This is more of a trial and error process although with more experience
you will get to the desired configuration more quickly.


Matt


Would you explain to me how/why you are doing ILS approaches above max
gear extended speed? (140KTS) Your post indicates that you held that
speed to DH.

That should have been 140 MPH. It is a 67 Arrow and thus has the
airspeed marked primarily in MPH and secondarily in knots and I forget
that now and then.

Happy now?


Matt

On Mon, 01 Jan 2007 17:26:12 GMT, Matt Whiting
wrote:

Bill Zaleski wrote:

On Mon, 01 Jan 2007 16:35:37 GMT, Matt Whiting
wrote:


facpi wrote:

Anyone give me a clue of the approach configuration of R172K? For
instance, now I use 100kts, 15inch, 2500RPM with no flaps for the
precision approach (ILS) for the training but it is not stable and too
fast for landing after DA.

I insist 90kts is good speed for the approach level and the precision
approach for R172K but my instructor suggested 100kts in terms of some
reason like the strong wind of winter.

I would appreciate if someone could show me the power setting of
approach configuration like non-precsion, precision, approach level
for
R172K. Thank you.

I like the recommendations made in Peter Dogan's book, The Instrument
Flight Training Manual. However, as your instructor said, there is no
single right power setting. If you assume no wind conditions, then a
90K approach speed works well as that yields close to 90 knots ground
speed (not exact due to the descent angle, but really close) which
matches up with one entry in the time charts for timed approaches.

However, given that you typically have at least some headwind, and more
in general in the winter as your instructor stated, if you figure a
nominal 10K headwind, then approaching at 100K airspeed again yields a
ground speed close to 90K which again makes it easy to pull the time

from the approach plate for approaches that are timed. And if you can't

land a 172 from 100K at a typical 200' ILS DH, then you need much more
practice.

It isn't unusual at larger airports to be asked to keep your speed up
for following traffic. I typically fly the ILS at 100K in the Arrow
that I fly, but I recently flew one at 140K due to a following RJ. It
really wasn't a big deal. I chopped the power at DH and had no problem
making a normal landing. Once you get "normal" approaches well in hand,
you want to go up and practice approaches at higher airspeeds so they
become familiar also.

This is the only area where I disagree a little with Dogan as he does
come across a little as suggesting that you can fill a card with 5 or 6
aircraft configurations and be happy ever after. The real world isn't
that simple. My primary instructor was an old-time seat of the pants
insructor as opposed to the more modern "by the numbers" philosophy.
Personally, I think both have their place. I use Dogan's by the numbers
approach to get a starting point, but then use whatever adjustments are
required to get the performance I need in the prevailing conditions.
This is more of a trial and error process although with more experience
you will get to the desired configuration more quickly.


Matt


Would you explain to me how/why you are doing ILS approaches above max
gear extended speed? (140KTS) Your post indicates that you held that
speed to DH.

That should have been 140 MPH. It is a 67 Arrow and thus has the
airspeed marked primarily in MPH and secondarily in knots and I forget
that now and then.

Happy now?


Matt

Sorry that I made the mistake of reading your post and replying to
what you said.

Bill Zaleski wrote:
Sorry that I made the mistake of reading your post and replying to
what you said.


Hangover?



--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com