Martinsville Approach

I know it's not considered good form to discuss or speculate on accidents
before the factual reports are released - however I'll bet I'm not the only
one who pulls up an approach plate when hearing about an accident on an IFR
approach. In my opinion, as long as the interest remains technical, and the
discussion respectful, we should not be held to any specious rule of silence
about accidents. Afer all, they are one of our best sources of learning, and
the primary source for rule-making - so it should be both natural and wise to
take an interest.

Looking at the RNAV approach plate for Martinsville, I notice that the missed
approach altitude is lower than the obstacle clearance altitude required to
make another approach. This means, after a missed, you would have to climb out
of the holding altitude to reach a safe altitude to make a second try on the
same approach. I thought that was contrary to TERPS procedures.

G Faris

On Tue, 26 Oct 2004 16:33:29 +0000 (UTC), (G Farris)
wrote:

I know it's not considered good form to discuss or speculate on accidents
before the factual reports are released - however I'll bet I'm not the only
one who pulls up an approach plate when hearing about an accident on an IFR
approach. In my opinion, as long as the interest remains technical, and the
discussion respectful, we should not be held to any specious rule of silence
about accidents. Afer all, they are one of our best sources of learning, and
the primary source for rule-making - so it should be both natural and wise to
take an interest.

Looking at the RNAV approach plate for Martinsville, I notice that the missed
approach altitude is lower than the obstacle clearance altitude required to
make another approach. This means, after a missed, you would have to climb out
of the holding altitude to reach a safe altitude to make a second try on the
same approach. I thought that was contrary to TERPS procedures.

G Faris

There are a number of airports in the country related to the name
"Martinsville". It would be helpful if you would post the ID for that
airport.
--ron

G Farris wrote:


Looking at the RNAV approach plate for Martinsville, I notice that the missed
approach altitude is lower than the obstacle clearance altitude required to
make another approach. This means, after a missed, you would have to climb out
of the holding altitude to reach a safe altitude to make a second try on the
same approach. I thought that was contrary to TERPS procedures.

I assume we're talking the RNAV 12 approach. Where the missed is to go to
ULAKE at 3000 but the initial is 5500.

The missed approach altitude is only necessary to provide safe transit from
the final approach segment to the holding fix (and to hold there). There's
no requirement to get from the holding fix back to an IAF to "have another
go". The vagaries in designing the missed approach involve the slop in the
pilots flying to follow the missed approach procedure.

What is telling is that if you start on the approach and don't make it to the
final segment, you're kind of in limbo when below the MSA if you need to bail.
Of course in this approach, that's sort of a moot point as the FAF is above the
missed approach altitude and everything is on a staight line from the IAF to the
holding fix.

Ron Rosenfeld wrote:
: There are a number of airports in the country related to the name
: "Martinsville". It would be helpful if you would post the ID for that
: airport.
: --ron

KMTV. It's about 50 miles south of where I'm sitting right now. It's right
on the edge of where the ridges of SW-VA fall off into the flatlands of NC. I flew
into BCB the day before to 500' OVC... pretty crappy weather and lots of rocks in the
clouds around here. No overt speculation, but I'm very interested to hear what the
investigation discovers.

-Cory
--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Ron Rosenfeld wrote:

G Faris


There are a number of airports in the country related to the name
"Martinsville". It would be helpful if you would post the ID for that
airport.
--ron

I believe he is referring to the MTV RNAV rwy 12 approach.
I think the airport is Blue Ridge or something like that.

"Ron Natalie" wrote in message
m...

What is telling is that if you start on the approach and don't make it to
the
final segment, you're kind of in limbo when below the MSA if you need to
bail.

I was taught to not initiate the missed approach procedure until reaching
the missed approach point for just this reason. The missed approach
procedure assumes you're starting from the MAP and provides obstacle
clearance accordingly.

-cwk.

On Tue, 26 Oct 2004 16:33:29 +0000 (UTC), (G Farris)
wrote:

I thought that was contrary to TERPS procedures.

What makes you think that?

What I see in TERPS is that the altitude needs to be sufficient to allow
*holding* or *enroute flight*.

Where do you see a requirement for an altitude high enough to start another
approach?


--ron

On Tue, 26 Oct 2004 18:26:07 +0000 (UTC),
wrote:

KMTV.

Thank you.
--ron

On Tue, 26 Oct 2004 14:26:49 -0400, Ron Natalie wrote:



I believe he is referring to the MTV RNAV rwy 12 approach.
I think the airport is Blue Ridge or something like that.

Thank you.
--ron

In article ,
says...


My apologies for being vague about the approach in question.
I didn't correct it because others cleared it up immediately.



I thought that was contrary to TERPS procedures.

What makes you think that?

What I see in TERPS is that the altitude needs to be sufficient to allow
*holding* or *enroute flight*.

Where do you see a requirement for an altitude high enough to start another
approach?



You're certainly right - It was the "en-route flight" phrase that made me
think the missed approach procedure had to take you above MSA. In practice,
I've seen missed approach holds that are slightly lower than the published
IAF's, but I can't remember seeing one where they hold you at an altitude that
does not provide terrain clearance in the immediate (10nm) vicinity of the
airport.

G Faris