non-vectored NDB IAF

"Gary Drescher" wrote in message news:9wn1d.296945$8_6.234657@attbi_s04...
"C Kingsbury" wrote in message
om...
I agree that final approach segments often demand higher precision
than what "the rules" require. My favorite is the ILS 5 to Lawrence,
MA, which ought to be called the cannonball run:

http://204.108.4.16/d-tpp/0409/00654I5.PDF

Hm, that's one of my favorite approaches to practice in LIFR. Flying it to
PTS standards looks safe to me. Is there a hazard I'm failing to appreciate?


No, not if flown properly. But, with the obstacles where they are, the
margin for error (particularly right around GRAPS where the
smokestacks are) is definitely reduced. I probably would not wait for
a full-scale right deflection before missing this approach if the
crosswinds were messing with my head.

It might be interesting sometime on a VFR day to fly this with the
localizer on its last dot (just barely not pegged) and also on the
last dot of the glideslope, just to see how much room that really
leaves you. Maybe I'll try it in Flight Simulator tonight just for
kicks.

Best,
-cwk.

"C Kingsbury" wrote in message
m...
"Gary Drescher" wrote in message
news:9wn1d.296945$8_6.234657@attbi_s04...
"C Kingsbury" wrote in message
om...
I agree that final approach segments often demand higher precision
than what "the rules" require. My favorite is the ILS 5 to Lawrence,
MA, which ought to be called the cannonball run:

http://204.108.4.16/d-tpp/0409/00654I5.PDF

Hm, that's one of my favorite approaches to practice in LIFR. Flying it
to
PTS standards looks safe to me. Is there a hazard I'm failing to
appreciate?


No, not if flown properly. But, with the obstacles where they are, the
margin for error (particularly right around GRAPS where the
smokestacks are) is definitely reduced.

True, but the obstacles are still well beyond both the horizontal and
vertical boundaries of the glideslope.

I probably would not wait for
a full-scale right deflection before missing this approach if the
crosswinds were messing with my head.

Yup, PTS standards call for no more than 3/4 deflection. I'd always go
missed in IMC if I were off by that much.

It might be interesting sometime on a VFR day to fly this with the
localizer on its last dot (just barely not pegged) and also on the
last dot of the glideslope, just to see how much room that really
leaves you. Maybe I'll try it in Flight Simulator tonight just for
kicks.

Cool, I'll give that a try too.

--Gary

"Gary Drescher" wrote
Yup, PTS standards call for no more than 3/4 deflection. I'd always go
missed in IMC if I were off by that much.

If you ever shoot the VOR-B at LVJ, half scale deflection (5-6
degrees) and a VOR that's off by 2 degrees (well within the acceptance
criteria) can be enough to kill you.

Michael

"Michael" wrote in message
om...
"Gary Drescher" wrote
Yup, PTS standards call for no more than 3/4 deflection. I'd always go
missed in IMC if I were off by that much.

If you ever shoot the VOR-B at LVJ, half scale deflection (5-6
degrees) and a VOR that's off by 2 degrees (well within the acceptance
criteria) can be enough to kill you.

Hm, the VOR could even be off by 6 degrees (for an in-air check) and still
be legal. In that case, even one dot of deflection could be lethal on that
approach.

--Gary

"Gary Drescher" wrote
Hm, the VOR could even be off by 6 degrees (for an in-air check) and still
be legal. In that case, even one dot of deflection could be lethal on that
approach.

Quite true. The scary part is I almost killed myself and a student
that way. We had a lesson one morning, I called for a briefing, and
there were two airports reporting IFR conditions. LVJ was the closer
one, so we went there (I'm a big believer in training in actual
whenever possible, even if it adds time to the lesson - owners tend to
be OK with that since they're just paying for gas) and the only
approaches were VOR and GPS. The plane had no GPS, but the VOR was
fine.

We got about 30 minutes of actual on the way out, but then the weather
started breaking up. Still, by the time we broke out we were being
vectored to the FAC so I had the student put the hood on and continue.

He was doing a fairly credible job of it (the air was bumpy) meaning
he was well within PTS standards at all times. And so I sat there and
watched as he performed an approach that should have been fine - and I
saw us head for a tower. Had we been in IMC, there is an excellent
chance I would not be here.

After this, we performed a VOR check in the air on this VOR. The VOR
showed 5 degrees off. In other words, it was legal. We later checked
it in the air on another VOR. On that one, it showed 2 degrees off.

Michael

(Michael) wrote in message . com...
"Gary Drescher" wrote
Yup, PTS standards call for no more than 3/4 deflection. I'd always go
missed in IMC if I were off by that much.

If you ever shoot the VOR-B at LVJ, half scale deflection (5-6
degrees) and a VOR that's off by 2 degrees (well within the acceptance
criteria) can be enough to kill you.

Michael

I searched around in the NTSB database to see if any such accidents
had ever happened, and wasn't able to find any. Which means that I
either did the search incorrectly, or no one's luck has run out yet. I
agree that it's well within the range of possibility.

-cwk.

(C Kingsbury) wrote
I searched around in the NTSB database to see if any such accidents
had ever happened, and wasn't able to find any. Which means that I
either did the search incorrectly, or no one's luck has run out yet. I
agree that it's well within the range of possibility.

I wonder how many of those CFIT accidents where the aircraft was
inexplicably off the FAC are actually a result of this.

I also don't think it's such a big deal anymore, because nobody I know
flies IFR without GPS, be it IFR certified or not.

Michael

"Michael" wrote in message
m...
I wonder how many of those CFIT accidents where the aircraft was
inexplicably off the FAC are actually a result of this.

I also don't think it's such a big deal anymore, because nobody I know
flies IFR without GPS, be it IFR certified or not.

I do. There's no GPS in most of the IFR planes I rent (but they do have VFR
LORAN).

--Gary

"C Kingsbury" wrote in message
m...
It might be interesting sometime on a VFR day to fly this with the
localizer on its last dot (just barely not pegged) and also on the
last dot of the glideslope, just to see how much room that really
leaves you. Maybe I'll try it in Flight Simulator tonight just for
kicks.

I tried it on FS2004. At full deflection, you certainly come close to a
smokestack, but you don't hit it. (Of course, the FS2004 scenery shouldn't
be trusted for real-world purposes, though it looks correct here.)

--Gary