GPS/WAAS VNAV approaches and runway length

LPV's are actually built to a TCH. If the airport has an ILS installed,
they'll aim for the same TCH. If they don't have ILS, they'll select a
TCH based on the wheel height group, which is based on the type of
aircraft expected at the runway. Wheel height groups can be found at the
following link, on page 19 of 70. The smaller the aircraft, the lower
the TCH requirement, which would make the touchdown point closer to the
threshold.
http://av-info.faa.gov/terps/Directi...es/8260.50.pdf

The tables in AC 150-5300-13 (pages 48/49 of 57) at
http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/f3e8f0f55c4ebcf986256e290071fd07/$FILE/AC150-5300-13chg6.pdf
give an idea of runway lengths required. 3058' doesn't meet the criteria
for LPV, so to answer your question, no LPV (unless criteria changes).

JPH

Nathan Young wrote:
The Garmin 480 now supports LPV approaches which are ILS like
approaches using WAAS-GPS for both LNAV and VNAV.

My question. I'm assuming the LPV approach would target 1000ft down
the runway as the TDZ (just like an ILS). Does this mean that LPV
approaches will not be added to the airports with smaller runways?

For example, my homefield (3ck)has a 3058 runway. The 1000 ft TDZ
would only leave 2000 ft to get stopped, so I am wondering if an LPV
approach would ever be added at 3ck (or similar airports).

On Fri, 22 Oct 2004 21:13:18 -0500, J Haggerty
wrote:

LPV's are actually built to a TCH. If the airport has an ILS installed,
they'll aim for the same TCH. If they don't have ILS, they'll select a
TCH based on the wheel height group, which is based on the type of
aircraft expected at the runway. Wheel height groups can be found at the
following link, on page 19 of 70. The smaller the aircraft, the lower
the TCH requirement, which would make the touchdown point closer to the
threshold.
http://av-info.faa.gov/terps/Directi...es/8260.50.pdf

The tables in AC 150-5300-13 (pages 48/49 of 57) at
http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgAdvisoryCircular.nsf/0/f3e8f0f55c4ebcf986256e290071fd07/$FILE/AC150-5300-13chg6.pdf
give an idea of runway lengths required. 3058' doesn't meet the criteria
for LPV, so to answer your question, no LPV (unless criteria changes).

Great references, thanks. I agree with your assessment - I don't
think 3ck can expect to benefit from one of these approaches anytime
soon. Too bad, as I would have liked the improved minimums... Not
that I would have used them much, but the piece of mind of having an
extra few hundred feet vs an alternate is nice.

-Nathan

Great references, thanks. I agree with your assessment - I don't
think 3ck can expect to benefit from one of these approaches anytime
soon. Too bad, as I would have liked the improved minimums..

I fly a Cessna 172. My ADF is not operating and my avionics shop suggested
removing and installing a Garmin 430.
Now I see that the 480 is available.
What do you guys think? 430 or 480?
Hank

"Hankal" wrote in message =
...
Great references, thanks. I agree with your assessment - I don't
think 3ck can expect to benefit from one of these approaches anytime
soon. Too bad, as I would have liked the improved minimums..
=20
I fly a Cessna 172. My ADF is not operating and my avionics shop =
suggested
removing and installing a Garmin 430.
Now I see that the 480 is available.
What do you guys think? 430 or 480?
Hank

There's a price difference, but the GNS-480/CNX-80 is hugely more =
capable.
---JRC---

There's a price difference, but the GNS-480/CNX-80 is hugely more =
capable.

I think about 2 grand, but waht is my life worth