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5Z
September 18th 09, 05:48 AM
One minute of LATITUDE is approximately a nautical mile. Use your
fingers as a crude caliper to measure distances on the chart.

Double the distance and multiply by 100 for 30:1
Triple the distance for 20:1

I'd set my GPS for STATUTE miles then use the above math while flying
the club's ASK-21 for a conservative glide for home.

Use an E6-B to calculate L/D. Some high end aviator watches have one.

Distance in NM vs altitude and the pointer indicates glide ration
needed to make the goal. Update every few miles and if the L/D
remains constant, then you're on glide. If it gets smaller, then you
have it in the bag.

I recall the huge amounts of heads down time in the pre-GPS days while
on a tight final glide or over unfamiliar terrain as I tried to figure
out precisely where I was.

-Tom

tstock
September 18th 09, 03:28 PM
On Sep 18, 12:48*am, 5Z > wrote:
> One minute of LATITUDE is approximately a nautical mile. *Use your
> fingers as a crude caliper to measure distances on the chart.
>
> Double the distance and multiply by 100 for 30:1
> Triple the distance for 20:1
>
> I'd set my GPS for STATUTE miles then use the above math while flying
> the club's ASK-21 for a conservative glide for home.
>
> Use an E6-B to calculate L/D. *Some high end aviator watches have one.
>
> Distance in NM vs altitude and the pointer indicates glide ration
> needed to make the goal. *Update every few miles and if the L/D
> remains constant, then you're on glide. *If it gets smaller, then you
> have it in the bag.
>
> I recall the huge amounts of heads down time in the pre-GPS days while
> on a tight final glide or over unfamiliar terrain as I tried to figure
> out precisely where I was.
>
> -Tom

Thanks for the tips, as a new glider pilot this is very useful info.

Tom

Andy[_1_]
September 18th 09, 08:24 PM
On Sep 18, 7:28*am, tstock > wrote:
>
> Thanks for the tips, as a new glider pilot this is very useful info.

Pre GPS I did rough glide estimates with my thumb. My thumb form
nucke to tip is about 10 miles and needs 2000ft

Andy[_1_]
September 18th 09, 08:32 PM
On Sep 18, 12:24*pm, Andy > wrote:
> On Sep 18, 7:28*am, tstock > wrote:
>
>
>
> > Thanks for the tips, as a new glider pilot this is very useful info.
>
> Pre GPS I did rough glide estimates with my thumb. *My thumb form
> nucke to tip is about 10 miles and needs 2000ft

Hit the wrong button!!!

Pre GPS I did rough glide estimates with my thumb. My thumb from
nuckle to tip is about 10NM and represents about 2000 ft required for
glide at 30:1. Just "pace" off the distance on a sectional and add
the required finish altitude.


Andy

ZZ
September 28th 09, 04:37 PM
Here is another...the typical human finger is approx. 5 NM wide.

Paul
ZZ


5Z wrote:
> One minute of LATITUDE is approximately a nautical mile. Use your
> fingers as a crude caliper to measure distances on the chart.
>
> Double the distance and multiply by 100 for 30:1
> Triple the distance for 20:1
>
> I'd set my GPS for STATUTE miles then use the above math while flying
> the club's ASK-21 for a conservative glide for home.
>
> Use an E6-B to calculate L/D. Some high end aviator watches have one.
>
> Distance in NM vs altitude and the pointer indicates glide ration
> needed to make the goal. Update every few miles and if the L/D
> remains constant, then you're on glide. If it gets smaller, then you
> have it in the bag.
>
> I recall the huge amounts of heads down time in the pre-GPS days while
> on a tight final glide or over unfamiliar terrain as I tried to figure
> out precisely where I was.
>
> -Tom

Jim White[_3_]
September 28th 09, 05:15 PM
My Garmin Pilot III has a vertical nav feature which will display Glide
Rate to Target on final glide. Its more accurate than judging the glide by
the goal position on the canopy. (hard to tell between 2 degrees - in - and
1.5 degrees - land out) If it is improving I speed up.

Jim



At 15:37 28 September 2009, ZZ wrote:
>Here is another...the typical human finger is approx. 5 NM wide.
>
>Paul
>ZZ
>
>
>5Z wrote:
>> One minute of LATITUDE is approximately a nautical mile. Use your
>> fingers as a crude caliper to measure distances on the chart.
>>
>> Double the distance and multiply by 100 for 30:1
>> Triple the distance for 20:1
>>
>> I'd set my GPS for STATUTE miles then use the above math while flying
>> the club's ASK-21 for a conservative glide for home.
>>
>> Use an E6-B to calculate L/D. Some high end aviator watches have one.
>>
>> Distance in NM vs altitude and the pointer indicates glide ration
>> needed to make the goal. Update every few miles and if the L/D
>> remains constant, then you're on glide. If it gets smaller, then you
>> have it in the bag.
>>
>> I recall the huge amounts of heads down time in the pre-GPS days while
>> on a tight final glide or over unfamiliar terrain as I tried to figure
>> out precisely where I was.
>>
>> -Tom
>

Nyal Williams[_2_]
September 28th 09, 07:00 PM
At 19:24 18 September 2009, Andy wrote:
>On Sep 18, 7:28=A0am, tstock wrote:
>>
>> Thanks for the tips, as a new glider pilot this is very useful info.
>
>Pre GPS I did rough glide estimates with my thumb. My thumb from nuckle
to tip is about 10 miles and needs 2000ft
>
At what altitude does this hold?

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