On Sep 28, 4:01*pm, Dave Nadler wrote:
On Sep 28, 5:02*pm, JJ Sinclair wrote:



I had a nasty land-out the other day, hit heavy sink while deep in the
mountains east of Williams, Ca. I lost 2500 feet in no time and found
myself below the mountain tops. Went to the 'Alternates' page on my
trusty SN-10 only to find I wasn't within gliding distance of any
listed alternates. I ran east following a canyon that lead to the
totally unlandable terrain east of Red Bluff. Down, down ,down I sank
maintaining about 1000 feet above the slope as I looked at nothing but
trees! Finally I flew over a small pasture that looked to be landable.
It had all my favorite attributes, short, bumpy, fenced, up hill with
trees on the approach end, but at the time, it looked lovely. Popped
the gear and turned down-wind at what looked to be about 800 feet,
pulled full spoiler just before the trees and cleared them by a good
10 feet. Flared with half spoiler and rolled about 10 feet when I hit
a mound that put the nose down hard (Genesis 2). I heard something pop
and then we were flying again. Pulled full spoiler and touched down
again and slid to a stop about 100 feet short of the fence. WOW, glad
that's over!
A few days later I checked my trace and found I was within easy
gliding distance of an airport (Ruth, Ca) when I hit all that sink.
Why didn't the SN-10 direct me to Ruth? Reading the manual, on page 21
it says; The 'A' attribute does not cause a point to appear in the
list of landable fields on the alternates page! Only points marked
with an 'L' for landable will be shown. Ruth was marked with an 'A'
only. Checking the local data bases I find Montague, Air Sailing,
Logan, Avenal, Hobbs and Parowan are all using *'A' without the 'L'
for landable airports.
Recommend everyone check to make sure the data base you are using with
the SN-10 has airports identified with an 'L' for landable attribure.
Cheers,
JJ
PS;The pop I heard on landing was a shear pin that fails when heavy
loads are placed on the nose wheel thereby preventing retraction loads
from being applied to the main gear. An easy fix after I located the
shear pin which is deep inside the nose wheel -well.

The "L" attribute is normally set by default for airports in the
databases I've seen - something funny is going on here.

HOWEVER: "L" is separate from "A" because:
- not all airports are landable, certainly not in larger-span gliders,
and
- other non-airport points in the DB can be landable.

You do need to check any database you load - whether into
an SN10, a PDA, or an electronic-picture-frame...

There are often errors in "official" databases.
Locally we have a listed airport that hasn't existed for a decade.
Bad news if you final-glide to this one.

Be careful out there,
Best Regards, Dave "YO electric"

I never fly anywhere without knowing beforehand the location of enough
landable fields or strips - a habit that goes way back before flight
computers and PDAs.

I guess flying a ship than can be cheerfully ground-looped without
breaking the tail off gives you a wider selection of non-landable
fields!

Mike