Landing Approach Glide Path Definition

[Peter G]

Dear Friends

preparing for the upcoming technical meeting of the F2 S/C,US member
Bill Lee has found an error in the wording of the Landing Manoeuvre
which currently says.

...The rate of descent should remain constant throughout the whole
gliding lap, from the moment that the model aircraft leaves...

Bill writes:

Quote:
The description of the landing maneuver does not reflect the desired
outcome. A constant rate of descent cannot be maintained when the
speed of the model is continuously slowing. The desired outcome is
that the model fly a smooth flight path with no waviness. Perhaps the
words should be “continuous downward slope” or similar. The diagram
reflects the desired outcome, the words do not.
End of quote

Please consider and comment the following options replacing "The rate
of descent should remain constant "

- The angle of descent should remain constant

- The angle of the glide path approach for landing should remain
constant

Or make own suggestions on exactly how to adjust the wording. Please
post your comments here, byhitting Replyat the bottom, before March
21.

Thank you and kind regards, Peter

[Joan McIntyre]

Hi Peter and fellow members,

I agree that the words" rate of descent" could be replaced in the landing
procedure.

I would probably prefer "the angle of the glide path approach for landing"
should remain constant .............
Kindest regards,

Joan McIntyre.

Dear Friends

Bill writes:

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[Keith Trostle]

I may be missing something here, but in my opinion, the landing is to be
performed where the descent is continuious with no "wavy flight". As a
judge, I would have a difficult time to ever determine if the "rate of
descent" was constant or the "angle of descent" was constant. After all,
the model is slowing down and its angle of attack is probably changing as
the model slows and descends. To me, the requirement should be that ther be
NO "wavy flight" where the model descends and ascends in some alternage
pattern. I do not think that the rule should specify any sort of "constatnt
rate" of descent or "constant angle" of descent.

Instead, some term like the flight path of the model should be continuously
descending flight

or something to the effect that:

the model should continuously descend from level flight altititude to touch
down.

Such wording would rule against a "wavy" landing approach and still allow
the pilot to perhaps flare just before the landing which could be assessed
as a smooth and very good landing maneuver.

Keith Trostle
Tucson, Arizona

USA

----- Original Message -----
From: "Peter G" <peterd...@bluewin.ch>
To: "F2B Group" <f2b-...@googlegroups.com>
Sent: Wednesday, March 17, 2010 3:53 AM
Subject: Landing Approach Glide Path Definition

Dear Friends

preparing for the upcoming technical meeting of the F2 S/C,US member
Bill Lee has found an error in the wording of the Landing Manoeuvre
which currently says.

...The rate of descent should remain constant throughout the whole
gliding lap, from the moment that the model aircraft leaves...

Bill writes:

Quote:
The description of the landing maneuver does not reflect the desired
outcome. A constant rate of descent cannot be maintained when the
speed of the model is continuously slowing. The desired outcome is
that the model fly a smooth flight path with no waviness. Perhaps the

words should be �continuous downward slope� or similar. The diagram

reflects the desired outcome, the words do not.
End of quote

Please consider and comment the following options replacing "The rate
of descent should remain constant "

- The angle of descent should remain constant

- The angle of the glide path approach for landing should remain
constant

Or make own suggestions on exactly how to adjust the wording. Please
post your comments here, byhitting Replyat the bottom, before March
21.

Thank you and kind regards, Peter

--

[Brett Buck]

On Mar 17, 2010, at 9:35 PM, Keith Trostle wrote:

> I may be missing something here, but in my opinion, the landing is
> to be performed where the descent is continuious with no "wavy
> flight". As a judge, I would have a difficult time to ever
> determine if the "rate of descent" was constant or the "angle of
> descent" was constant. After all, the model is slowing down and its
> angle of attack is probably changing as the model slows and descends.

And, of course, if you do it right, it doesn't slow down very much
at all, so the two variations approach the same thing.

If we want to mess with the description of the landing, might I
suggest that instead of the angle, we ought to address the "one lap"
rule. It seems unnecessary to require the distance to be one lap - the
goal is to land with no significant changes in the approach. Despite
what some say, it *is* possible, even easy, to get the lap, but why is
it important?

Brett

[Keith Renecle]

You could just state : "........a smooth descent......"

I would also agree with Brett that the required one lap has caused more
problems than its worth, especially in bad weather. It's something like the
starting point of the clover that we have now solved. Where exactly is that
point where it crosses the level flight line as the model descends?? All of
us have seen how many competitors try to drag the model around all over the
place trying to get in that one lap, instead of just putting the model down
smoothly in a shorter distance. Here I believe that the AMA rules are much
more sensible. Maybe this is a good time to fix this now?

Regards,

Keith R

[Joan McIntyre]

Hi guys,

Having looked at your responses, Brett, Keith and Keith R., I believe that
that would be the better option.

What we are really looking for is, as Keith says, a smooth descent. I, too,
have often questioned the necessity of the "one lap", the exact starting
point of which is almost impossible for any two judges to agree upon. It
also causes the greatest problem, when pilots try to extend the glide to
where they consider is one complete lap, and in the process, lose any
semblance of the smooth descent altogether.

Perhaps it may be appropriate to omit any prescribed distance, and enable
pilots to concentrate on a smooth, controlled landing.

Kind regards,

Joan McIntyre.

-----Original Message-----
From: f2b-...@googlegroups.com [mailto:f2b-...@googlegroups.com] On

[Igor Burger]

Hi All,

I thing the "one lap" rule is often overestimated. I think that since we
have some from - to in level definition, judge must allow that from - to to
be begin of the maneuver, so the target for landing is not single point, it
is also so from - to and its projection to ground under such small angle can
be easily up to 1/4 of lap.

I am not sure if we should keep it or not, so I am not advocating that rule,
but I see good reasons in previous posts to delete it, so I will add good
reasons to keep it:

- it is the only maneuver where we move our bones little bit :-)
- the "one lap" rule is one of few when pilot must thing two or more laps in
advance what he will do (especially in wind like Keith mentioned) in
contrast with memorized and automated maneuvers like square eight which can
everyone do with closed eyes
- it makes the maneuver little more complicated, so pilot can better show
what he can do
- I think we should not make pattern easier, because pilots should show more
and judges observe more and decide more, because we have too small
differences in final scores ... like we define eight which is eight, and
also of some size, and also of proper intersection, and also twice on the
same place ... so similar we can have smooth landing, which is also one lap
long ... simple :-)

igor

[Kim Doherty]

Now we are getting somewhere!

This:

" Perhaps it may be appropriate to omit any prescribed distance, and enable
pilots to concentrate on a smooth, controlled landing."

Is the correct "approach" and will save more planes from disaster than
changing the entry or exit from the clover IMHO.

Thanks,

Kim.

[aagewiberg]

Hi all.

I am also in favour of a natural descend after engine quits powering the
models. In Landres for example you could have to come so near the edge of
the concrete inner circle at the grass circle that you might hurt a leg
"desperately" trying to have a full lap of descend. Also rules can force you
to land downwind which sometimes requires a lot of pulling in bad wind, and
have a touch down with high speed on grass. No 1/1 airplane would seek such
a landing downwind.

Aage

-----Oprindelig meddelelse-----
Fra: f2b-...@googlegroups.com [mailto:f2b-...@googlegroups.com] På vegne
af Joan McIntyre
Sendt: 18. marts 2010 07:52
Til: f2b-...@googlegroups.com
Emne: RE: Landing Approach Glide Path Definition

[Peter G]

Dear all

please allow me to add the following procedural explanations:

a.) The incorrect "rate of descent" defintion is part of the the
revised descripition of all manoeuvres recently submitted to the
Delegates and the members of the s/c for voting at the upcoming
Plenary Meeting in April. As you will rembember, this revision was
made to comply with the principle of no longer flying parallel to
ground. Because this change of paradigm has been so far approved by
the members of the s/c we now stand a very good chance of acceptance
by the Plenary Meeting. A minor adjustement, such as the replacement
of "rate of descent" by a more accurate definition, cannot not be
considered as a rule change and it could be made during the s/c
technical meeting preceeding the Plenary,thus becoming part of the
rule by January 1st 2011.

b.) When it comes to submit a rule change, such as "no one lap landing
approach" we need follow established procedures which are:

1.) Undertake opinion research within the F2B community (here on this
page, for example)

2.) Find consus on whether and/or how to change the rule.

3.) Prepare a related change proposal.

4.) Submit the proposal, together with the result of 1.), to the
chairman of the F2 s/c by November 15th 2010, latest.

Alternatively, each NAC is entitled to submit its own proposal, by the
same deadline.

Here is what this means for us today:

c.) Being no rule change, we can rectify the "rate of descent" issue
and need to find consenus on how to do it.

d.) It is too late to submit a "no on elap" rule change proposal for
the April 16/17 2010 Plenary Meeting. The next deadline to do so is
Nov. 15th 2010.

e.) We should start discussing the one lap issue. I will open a
related discussion thread in near future, inviting those who have
already commented to re-post there.

Kind regards,

[Peter G]

Dear All

As I am supposed to reply, regarding Bill Lee's comment on "rate of
descent",to the Chairman of the F2 S/C, I would like to have your
opinion on Keith Trostle's input which would come down to a wording
like this:

------
b. The descent segment:
The model should fly for 1 full gliding lap with the motor/s and
propeller/s stopped. This lap is measured from the start of the
descent from the height of the base (+/- 30cm) until the point of
touchdown. The model should continously descend from level flight to
touch down. The touch down itself should be smooth and either a “2
point” or a “3 point” touch down shall be judged as equally correct.
------

Being of strictly technical corrective nature, I am positive that the
S/C will approve the incorporation of this clarification into the
current proposal. (Annex 7a S-C F2B 4.2.15.3 - 4.2.15.17, page 17)

Please comment in order for me to bring forward the F2B Group point of
view to the S/C.

Kind regards,

[Bill Lee]

Hello, all;

I spoke with Keith on this issue and what is shown below is essentially what we came up with. My only concern is the definition of the words "continuously descend".

I am sure that there are those who will contend that there are many flight paths that can be described as "continuously descending" but are simply NOT what we want for the flight path of the landing maneuver. A landing path which is not straight but always descending (e.g., a "wavering" path) is most definitely "continuously descending" but not correct.

As well, one must always separate the concept of the "flight path" from the "model orientation". E.g., a small flare at the end of the landing approach to facilitate touchdown is a change in the orientation of the model relative to the flight path, but need NOT be a deviation from a straight flight path.� E.g., as the model slows it is required that the angle of attack of the model must also change in order to maintain a given flight path. Judges must be aware of these differences.

I suggest that the sentence

The model should continously descend from level flight to
touch down.

be modified to read

The model should continuously descend from level flight to
touch down with no deviation from a straight flight path.

Regards,

Bill Lee

On 03/22/2010 09:23 AM, Peter G wrote:

Dear All

As I am supposed to reply, regarding Bill Lee's comment on "rate of
descent",to the Chairman of the F2 S/C, I would like to have your
opinion on Keith Trostle's input which would come down to a wording
like this:

------
b. The descent segment:
The model should fly for 1 full gliding lap with the motor/s and
propeller/s stopped. This lap is measured from the start of the
descent from the height of the base (+/- 30cm) until the point of
touchdown. The model should continously descend from level flight to
touch down. The touch down itself should be smooth and either a �2
point� or a �3 point� touch down shall be judged as equally correct.
------

Being of strictly technical corrective nature, I am positive that the
S/C will approve the incorporation of this clarification into the
current proposal. (Annex 7a S-C F2B 4.2.15.3 -  4.2.15.17, page 17)

Please comment in order for me to bring forward the F2B Group point of
view to the S/C.

Kind regards,




...The rate of descent should remain constant throughout the whole
gliding lap, from the moment that the model aircraft leaves...



  

[Peter G]

Closing message

Dear Friends

Thank you for contributing to the „rate of descent issue“ I will
compile your comments and forward the following recommendation to the
F2 Subcommitee:

4.2.15.17. Landing Manoeuvre

b) The descent segment

The model should fly for 1 full gliding lap with the motor/s and
propeller/s stopped. This lap is measured from the start of the
descent from the height of the base (+/- 30cm) until the point of

touchdown. The model should continuously descend from level flight to
touch down with no deviation from a straight flight path. The touch

down itself should be smooth and either a “2 point” or a “3 point”

touch down shall be judged as equally correct.
--

Please carry on contributing to the one lap glide issue under „One Lap
Landing Approach“. It would definitely be of value to hear about the
view of FAI flyers/judges in particular.

Kind regards

[Brett Buck]

How would one go about returning to conventional aviation country
ID prefixes (i.e. "N" instead of "USA", etc)? This is an aviation-
based sport, and it's not likely to be added to the Olympics any time
soon, so it makes more sense to use the standard ID.

Brett

[go_s...@comcast.net]

I would talk to Peter Greman to see if anything can be added to their upcoming discussions at the FAI.

 

Paul

----- Original Message -----
From: "Brett Buck" <buc...@pacbell.net>
To: f2b-...@googlegroups.com

[Peter G]

Brett, I must admit that I have no really good answer on how to
proceed. However, as this is an issue being relevant for all category
model airplanes, I would like to suggest to inquire with your national
delegate to CIAM (David G. Brown). I am positive he will be glad to
explain in detail the reasons for the current ID system.

Peter

[Brett Buck]

On Mar 31, 2010, at 4:06 AM, Peter G wrote:

> Brett, I must admit that I have no really good answer on how to
> proceed. However, as this is an issue being relevant for all category
> model airplanes, I would like to suggest to inquire with your national
> delegate to CIAM (David G. Brown). I am positive he will be glad to
> explain in detail the reasons for the current ID system.

I think I get the reasoning, but I don't think it is correct.
Where can I find FAI Rules Proposal forms?

Brett

[Bill Lee]

Brett, the best way to handle this is to work with your national delegate to the CIAM (Dave Brown) or more specifically the F2 Technical Subcommittee representative (me). We have the process for making rules proposals well in hand. Just keep in mind that the CIAM works on a rather rigorous schedule where proposals have to be submitted well in advance of the meetings where they are considered. The next opportunity for rules change proposals will end November 15 of this year, for possible consideration at the 2011 CIAM meetings.

To answer your question specifically: on page http://www.fai.org/aeromodelling/documents/forms you will find this: "Note: the CIAM Proposal Form and Guidelines have been temporarily withdrawn and will be available again in May 2010." I believe this is what you will want, just not available now.

(Peter and others: please correct me if I am wrong on the process and schedule.)

Regards,

Bill Lee