Final glide

On Tue, 24 Sep 2019 07:44:48 -0700, waremark wrote:

I am interested by the point about the reserve being added to your
finish height where your finish height is different from your arrival
height at an airfield. How does this work? I don't have 'Finish is
1,000m below start set' as it doesn't normally affect me - if I start
above 1,000 m on a flight for which the scoring will be affected that is
another adjustment which I make mentally. In the UK the rule does not
affect competition scoring but does affect our BGA Ladder. I have never
flown with a finish other than at an airfield - is there a way to set
the minimum height at a finish ring?

I use LK8000 as my main navigation tool. It displays arrival heights as a
signed value, which is difference from your configured arrival height. So
with 1000 configured as your target arrival height, if it displays +200
its predicting you'll arrive 200 ft above target and if it shows -400 its
predicting arrival 400 ft below target.

That works for me.


--
Martin | martin at
Gregorie | gregorie dot org

I'm stuck back in 1986 (87, actually).Â* I set my CNII to arrive at
1,000' AGL over mid field and it never works out for me.Â* I get lower
and lower and, as I get nervous, I arrive well above where I want to be.

I can set the XCSoar unit to Automatic McCready and it directs scary
fast speeds with MC 9.0 or more.

So, Evan, precisely how do you read your expected arrival height after
setting your safety factor to zero?Â* I'd like to give it a try.

On 9/23/2019 8:01 PM, Tango Eight wrote:
O
It was dumb in 1986 too :-).

No one arrival height covers all situations.

T8
Of course not but it is still personal a personal preference, no need to be opiniated, there is always more than one way to skin a cat.
Try it the other way, you'll see.

Happy landings,
T8

--
Dan, 5J

Now I get it!Â* My glide slope indication is what I'm interested in.
Since I maintain a 1,000' AGL arrival height in my settings, I look at
the glide slope indication as, "At what altitude will arrive over the
field?".Â* The only difference is, then, with my arrival height I know
that, as the glide slope approaches zero, I should arrive over the field
at 1,000', which is what I want.Â* If I set zero as my arrival height, I
must remember to think that this is the altitude that I'll arrive and
then think, "Will I have enough altitude to fly a proper pattern?"Â*
Neither method is very difficult, just a matter of preference.Â* On my
last flight, from 5 miles out, I said I'd be making a right base entry
to the runway whereas the normal pattern is to the left.Â* It was more
like a 45 degree base leg.

On 9/24/2019 5:32 AM, RR wrote:
Steve has mentioned the key here. If you are about to head home, and find yourself saying somthing like the following, "I am 1000 over, my 1000ft reserve" then your reserve is doing you a disservice. It is somewhat of catch 22. You need to be aware of your reserve in case things go south and you fall below it, but the purpose is to keep you from needing to think about it (always have 1000 ft in reserve).

The biggest problem is when things go south. If you are close in, you fall below 0, now you need to subtract from your reserve to figure out your true arrival height. If you use somthing other than 1000 ft it gets harder. So right when you most need clear information you are doing mental math. Bad timing to insert a math problem before you need to make a critical decision. Some (in the admiralty), if not most, know how I know this.

It has been described as setting your watch ahead so you are not late.

I too had flown with a reserve for years, and was worried about switching, but just a few flights and you adjust. And a few more and you realy start to appreciate the fact that you are, for the first time, realy getting the number you want out of your flight computer.

How high will I be when I get there...

RR
Commodore

--
Dan, 5J

At 14:44 24 September 2019, waremark wrote:
In the UK the rule does not affect competition scoring but
do=
es affect our BGA Ladder. I have never flown with a finish other than
at
an=
airfield - is there a way to set the minimum height at a finish ring?

With LXxxxx, just set the finish ring radius and a "safety height" of
500ft or whatever on the QNH page. The LX will then show the arrival
height margin at the ring, not the airfield. 0ft on the LX means you are
at the set ring-crossing height.

MC

And then you land out before arriving at the airfield! I cannot understand why people ever set finish rings at a height which isn't sufficient to ensure a comfortable arrival at the airfield.

On Tue, 24 Sep 2019 15:30:42 -0700, waremark wrote:

And then you land out before arriving at the airfield! I cannot
understand why people ever set finish rings at a height which isn't
sufficient to ensure a comfortable arrival at the airfield.

Looks reasonable to me: just set a small finish ring, say with a radius
equal to the distance from the airfield TP to the high key point for the
run being used on that day and ring height to what the destructors like
as high key height. That should be pretty close to putting you at the
start of what amounts to a text-book approach.

I'd try it myself, provided there's another flying day hiding amidst the
current rain and wind. However, although LK8000 7.0 allows a finish ring
to be specified, it doesn't allow a finish height to be input.

I feel a change request coming on....


--
Martin | martin at
Gregorie | gregorie dot org

Now who ever said making the perfect final glide was suppossed to be "comfortable" lol. If it is too comfortable you just left points on the table.

On Tuesday, September 24, 2019 at 4:36:30 PM UTC-7, wrote:
Now who ever said making the perfect final glide was suppossed to be "comfortable" lol. If it is too comfortable you just left points on the table.

I would be extremely nervous about making a final glide that would have me doing a straight-in final at max L/D. Under this scenario, if your glide computer is very accurate, half of the time you would be landing short. And anywhere I fly, landing short is not an option. I am with Mike: I don't regard it as a reserve, that IS the altitude that I want to arrive at. My real reserve is the altitude I have over that. Too many times I have seen that reserve evaporate along the way. You may encounter unexpected areas of sink or stronger headwinds than expected.

Tom

Truth, and a final glide made at max l/d tells me that the guy already screwed up. The perfect final glide is one that gets you home at the proper altitude and at the max speed. He just screwed up on both counts.

On Tuesday, September 24, 2019 at 5:14:29 PM UTC-7, wrote:
Truth, and a final glide made at max l/d tells me that the guy already screwed up. The perfect final glide is one that gets you home at the proper altitude and at the max speed. He just screwed up on both counts.

Yeah, RIGHT! How often do you get the "perfect" final glide? You, sir, are the one that's screwed up!

Tom