GPS approach safety case

wrote in message
...
Julian, so what is the reason no gps approaches in the UK?
What is the CAA waiting for?
Are there not some fields that could benefit from an approach that can
be lined up exactly with the centerline?
Is it only politics?

Good questions. I'd rather not put words into the CAA's mouth. I just want
to ask the questions once armed with the safety case!

Julian

On Sun, 6 Jun 2004 19:11:38 +0100, "Julian Scarfe"
wrote:

"S Green" wrote in message
...

tend to agree. Look who controls the GPS infrastructure. without
assurances
that the integrity of the system was not at the whim of the US Department
of
Defence, I cannot see the UK authorities being prepared to rely on GPS.
Ultimately this does become a safety issue.

But the UK authorities already rely on GPS at least to the same extent. As
well as having to carry ADF, VOR and DME for IFR flight in controlled
airspace, anyone wanting to fly at or above FL100 (note that that's
equivalent to 10,000 ft, perhaps not what US pilots are used to for flight
levels) needs B-RNAV (B for Basic). The only economical way of meeting the
B-RNAV requirement is to carry a TSO-C129a class A GPS receiver. I have in

Here I have basick RNAV and it doesn't even have a GPS input.
Strictly the old KNS-80, but it is RNAV ... over here.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

the back of my mind that, ironically, it has to be class A1 (approach
capable) because B-RNAV imposes some extra requirements beyond the A2 spec,
but I'm not sure. Thus if the GPS infrastructure disappears, the
unavailability of a few overlay approaches or even standalone GPS approaches
is the least of our problems!

I'd like to see:

a) a relaxation in the requirement to carry all of ADF, VOR *and* DME if
there's also a TSO-C129a GPS receiver and the conventional nav equipment
allows sensible backup.

b) the ability to fly overlay NDB approaches without ADF, again provided nav
equipment is carried to enable an approach at an alternate.

Sometimes, and I know its rare, politics falls before a rational argument...

Julian Scarfe

"Roger Halstead" wrote in message
...

Here I have basick RNAV and it doesn't even have a GPS input.
Strictly the old KNS-80, but it is RNAV ... over here.

We have one too, and it bought us an exemption for a few years. But it
doesn't meet current B-RNAV requirements for two reasons:

1) Its VOR is no longer approved for IFR use in Europe, since it doesn't
meet FM-immunity requirements -- I think they made a filter kit for the
upgrade to FM immune, but its cost was a serious fraction of the cost of a
TSO-C129a GPS!

2) B-RNAV equipment has to have a waypoint database, so that when they sent
you to FOOBA the nav kit knows where you're going, even if you don't.

Julian

S Green wrote:


tend to agree. Look who controls the GPS infrastructure. without assurances
that the integrity of the system was not at the whim of the US Department of
Defence, I cannot see the UK authorities being prepared to rely on GPS.
Ultimately this does become a safety issue.

What the US authorities do in their own country and to their own airspace
system is one thing, doing it in someone else's is another.

That is such a crock of crap. The politics I am referring to is the refusal of
you Brits to take a freebie and run with it.

You don't have to dissasemble your present system, yet take advantage of GPS for
superior non-precision IAPs all over the Empire. If the evil Americans shut
down the system you treat it like a RAIM failure and proceed to your non-GPS
alternate.

S Green wrote:

wrote in message ...


Julian Scarfe wrote:


10ish years after overlay GPS approaches were introduced in the US, we

in

the UK still have no GPS approaches. There must be a considerable body

of

evidence collected on accidents, incidents and anomalies over the period
that GPS approaches have been in use. In particular, there may be

evidence

that GPS approaches have improved overall safety in non-precision
approaches.

Any pointers please?

No pointers. Emprically, I'd say they are working great in the US. The

issue

is politics, not safety.


tend to agree. Look who controls the GPS infrastructure. without assurances
that the integrity of the system was not at the whim of the US Department of
Defence, I cannot see the UK authorities being prepared to rely on GPS.
Ultimately this does become a safety issue.

I think it is still politics.


What the US authorities do in their own country and to their own airspace
system is one thing, doing it in someone else's is another.

Do you really think the US would do something that would jeopardize its
own civilian traffic? Also, there are reasons that most aircraft have
multiple navigation systems. Any system can fail and it is only prudent
to have some form of backup. If any country depends only on GPS for
navigation, then the safety issue is theirs.


Matt

Google "eurofix" to get a glimpse of the future.

Bob Gardner

"Julian Scarfe" wrote in message
news:S3Awc.214$SC4.162@newsfe5-win...
10ish years after overlay GPS approaches were introduced in the US, we in
the UK still have no GPS approaches. There must be a considerable body of
evidence collected on accidents, incidents and anomalies over the period
that GPS approaches have been in use. In particular, there may be
evidence
that GPS approaches have improved overall safety in non-precision
approaches.

Any pointers please?

Thanks

Julian Scarfe

"Bob Gardner" wrote in message
...
Google "eurofix" to get a glimpse of the future.

Interesting, though it doesn't appear to have been updated for three years
(including the "live" test data)!

Julian

OK, then, go to www.avionicsmagazine.com, June 2004 issue, and see the
future. My point is that within a few years, enhanced loran will be
available when GPS is not.

Bob Gardner

"Julian Scarfe" wrote in message
news:atLwc.293$%a5.124@newsfe5-win...
"Bob Gardner" wrote in message
...
Google "eurofix" to get a glimpse of the future.

Interesting, though it doesn't appear to have been updated for three years
(including the "live" test data)!

Julian

On Sun, 6 Jun 2004 18:22:59 -0700, "Bob Gardner"
wrote:

OK, then, go to www.avionicsmagazine.com, June 2004 issue, and see the
future. My point is that within a few years, enhanced loran will be
available when GPS is not.

What is enhanced Loran? I've used the old Loran for years and have
developed a healthy distrust of its accuracy. It is handy and easy to
use, but I always want something to prove it's correct.

Multipathing, atmospherics, signal failure, complete loss of
navigation from the loran, 2 miles changes in position when changing
chains, and one time it had me at the wrong airport 20 miles from the
desired one. When I headed for home 2 hours later it still was
figuring I was in the wrong place. About 5 miles after I started
south it did a reset and low and behold, I was not back on course.
:-))

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

Bob Gardner

"Julian Scarfe" wrote in message
news:atLwc.293$%a5.124@newsfe5-win...
"Bob Gardner" wrote in message
...
Google "eurofix" to get a glimpse of the future.

Interesting, though it doesn't appear to have been updated for three years
(including the "live" test data)!

Julian

Roger, you and C. J. Campbell are referring to what is now known as legacy
loran. Enhanced loran timing has an accuracy of one nanosecond, compared to
the timers I used when I was in the USCG. New antennas, using the H-field,
have eliminated the effects of precipitation static. New "all-in-view"
receivers work with 30 to 40 stations simultaneously, obviating the need for
the pilot to select chains or be concerned with station geometry. It's a
whole new technology that should not be compared to legacy loran.

Go to http://www.locusinc.com/library/2004ICNS.pdf and you will see the
result of test flights showing the enhanced loran track overlying the GPS
track within a microscrump.

Bob Gardner

"Roger Halstead" wrote in message
...
On Sun, 6 Jun 2004 18:22:59 -0700, "Bob Gardner"
wrote:

OK, then, go to www.avionicsmagazine.com, June 2004 issue, and see the
future. My point is that within a few years, enhanced loran will be
available when GPS is not.

What is enhanced Loran? I've used the old Loran for years and have
developed a healthy distrust of its accuracy. It is handy and easy to
use, but I always want something to prove it's correct.

Multipathing, atmospherics, signal failure, complete loss of
navigation from the loran, 2 miles changes in position when changing
chains, and one time it had me at the wrong airport 20 miles from the
desired one. When I headed for home 2 hours later it still was
figuring I was in the wrong place. About 5 miles after I started
south it did a reset and low and behold, I was not back on course.
:-))

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

Bob Gardner

"Julian Scarfe" wrote in message
news:atLwc.293$%a5.124@newsfe5-win...
"Bob Gardner" wrote in message
...
Google "eurofix" to get a glimpse of the future.

Interesting, though it doesn't appear to have been updated for three
years
(including the "live" test data)!

Julian