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December 23rd 04, 12:04 PM
Most RNAV approaches have the notations:

"GPS or RNP - 0.3 required", and
"DME/DME RNP - 0.3 not authorized"

1. The "or RNP .3" seems to imply some navigation unit other than gps
can have rnp .3 Any idea what?

2. If an FMS with rnp .3 is able to conduct this approach, wouldn't
it need a gps input to be that accurate? Surely IRS with dme updating
can't be used for any non prec approach?

2. Any approaches where dme/dme rnp .3 IS authorized?

Stan

December 23rd 04, 12:44 PM
wrote:

> Most RNAV approaches have the notations:
>
> "GPS or RNP - 0.3 required", and
> "DME/DME RNP - 0.3 not authorized"
>
> 1. The "or RNP .3" seems to imply some navigation unit other than gps
> can have rnp .3 Any idea what?

There is this "fairyland" concept that RNP is sensor independent. This is
true for large numbers, where INS or IRUs will provide the integrity and
accuracy required. But, with small values such as RNO 0.3, it is almost
impossible to satisfy the RNP qualification requirements without GPS as
the primary sensor.

>
>
> 2. If an FMS with rnp .3 is able to conduct this approach, wouldn't
> it need a gps input to be that accurate? Surely IRS with dme updating
> can't be used for any non prec approach?

The airline industry conned the FAA to let them use IRUs and DME/DME for a
couple of years, until some dramatic map shifts almost caused a couple of
CFIT accidents.

>
>
> 2. Any approaches where dme/dme rnp .3 IS authorized?
>

Only with specials at a few locations with very robust DME reception down
in the weeds. There are no public procedures.

Gene Whitt
December 24th 04, 05:53 AM
Y'All,
The following is just a small sample of a mix of need to know, nice to know
and what to know. The fact that there is also a diagram in the book makes
it more understandable. I believe that the .3 RNP level and lower can only
be reached with WAAS or LAAS still in the works.

RNP stands for Required Navigational Performance. This is described and
illustrated on Page 1-13 of the
2004 FAA-H8261-1 Instrrument Procedures Handbook. What follows is just the
INTRODUCTION. Test
questions will be based on material from subsequent chapters.

---.3RPN is the 3/10 of a nautical mile to each side of the final approach
course center line required for aircraft and equipment certification. This
is both a performance and functional requirement.for IFR certification

---The total system error (TSE) allowed in the final approach airspace due
to navigational system errors (NSE) includes computation errors, display
errors and flight technical errors (FTE) must not exceed .3 of a nautical
mile to either side of the final approach course center line.as laid out in
the ICAO Manual (Doc 9613). These .3 RNP on the final approach course (FAC)
and for the following air route areas must be both repeatable and
predictable to the declared levels of accuracy. For departure (1.0 RNP),
RNP 2.0.enroute, RNP 1.0 termina arrival and RNP 0.3 approach.

---The International Civil Aviation Organization (ICAO) uses RNP type for
airspace known as RNP-.0, RNP-4.0,
RPN-5.0 and RNP-10.0 The required performance is obtained through a
combination of aircraft capability and level of service provided by the
navigation infrastructor

---The following equation applies: Aircraft Capability + Level of Service =
Access

---RPN 0.3 is the lowest U.S. normal RNAV operation but special procedures
procedures use lower RNP levels.

Sample questions
1.What parts of the NAS have the same RPN?

2. What factors are included in finding the TSE due to NSE besidesFTE?

3. What part does the air route play in RNAV RNP levels?

4. Where do the ICAO and NAS have common RNPs?

5. How does the RNP 2.0 relate to airway width?

Mike Rapoport
December 24th 04, 09:56 PM
Why do you think that .3nm RNP can only be achieved with WAAS or LAAS?

MIke
MU-2


"Gene Whitt" > wrote in message
nk.net...
> Y'All,
> The following is just a small sample of a mix of need to know, nice to
> know and what to know. The fact that there is also a diagram in the book
> makes it more understandable. I believe that the .3 RNP level and lower
> can only be reached with WAAS or LAAS still in the works.
>
> RNP stands for Required Navigational Performance. This is described and
> illustrated on Page 1-13 of the
> 2004 FAA-H8261-1 Instrrument Procedures Handbook. What follows is just
> the INTRODUCTION. Test
> questions will be based on material from subsequent chapters.
>
> ---.3RPN is the 3/10 of a nautical mile to each side of the final approach
> course center line required for aircraft and equipment certification.
> This is both a performance and functional requirement.for IFR
> certification
>
> ---The total system error (TSE) allowed in the final approach airspace due
> to navigational system errors (NSE) includes computation errors, display
> errors and flight technical errors (FTE) must not exceed .3 of a nautical
> mile to either side of the final approach course center line.as laid out
> in the ICAO Manual (Doc 9613). These .3 RNP on the final approach course
> (FAC) and for the following air route areas must be both repeatable and
> predictable to the declared levels of accuracy. For departure (1.0 RNP),
> RNP 2.0.enroute, RNP 1.0 termina arrival and RNP 0.3 approach.
>
> ---The International Civil Aviation Organization (ICAO) uses RNP type for
> airspace known as RNP-.0, RNP-4.0,
> RPN-5.0 and RNP-10.0 The required performance is obtained through a
> combination of aircraft capability and level of service provided by the
> navigation infrastructor
>
> ---The following equation applies: Aircraft Capability + Level of Service
> = Access
>
> ---RPN 0.3 is the lowest U.S. normal RNAV operation but special procedures
> procedures use lower RNP levels.
>
> Sample questions
> 1.What parts of the NAS have the same RPN?
>
> 2. What factors are included in finding the TSE due to NSE besidesFTE?
>
> 3. What part does the air route play in RNAV RNP levels?
>
> 4. Where do the ICAO and NAS have common RNPs?
>
> 5. How does the RNP 2.0 relate to airway width?
>
>
>
>

December 25th 04, 12:53 AM
Gene Whitt wrote:

> Y'All,
> The following is just a small sample of a mix of need to know, nice to know
> and what to know. The fact that there is also a diagram in the book makes
> it more understandable. I believe that the .3 RNP level and lower can only
> be reached with WAAS or LAAS still in the works.

That is incorrect. Today's RNAV IAPs are considered RNP 0.3 procedures but they
don't use linear containment areas.

Draft criteria for linear RNP containment area procedures to values as low as
0.10 and optionally using RF/TF legs has been completed by the FAA/Industry PARC
(performance-based advanced procedures group) and is awaiting signature from the
head shed.

WAAS will be required on these procedures only if an LPV glide path is to be
designed into the procedure. With BARO VNAV, no WAAS requirement.

Gene Whitt
December 25th 04, 04:21 AM
Y'All,
Tim and Mike are correct in that I was making an assumption as to the
accuracy of the GPS RNP-0.3 Minimum Aviation System Performance
Specifications (MASPS). As with practically all FAA
standards they only establish minimums. The .3 minimums need exist
only 95% of the time and they may not be linear but the diagrams
used to illustrate the RNPs use lises. (Figure 1-11 on page 1-13)

I am not a great believer in the validity of FAA minimums when my
flying life is at risk.
Gene Whitt

December 25th 04, 08:48 AM
Gene Whitt wrote:

> I am not a great believer in the validity of FAA minimums when my
> flying life is at risk.
> Gene Whitt

Minimum standards are minimums, such as MDAs and DAs?

RNP takes a lot of the determination of system performance away from the
FAA and into the hands of the operator. With a well-trained crew in the
latest Falcons or Gulfstreams, for instance, it's accurate, has abundant
integrety, and far better than anything the FAA has ever offered, except
for the better instrument landing systems.

December 26th 04, 06:39 PM
Thanks Tim and Gene for you insights. I'm told Alaska Airlines has
rnp .1 approval for some approaches up there. I presume this must be
IRS (for smoothing) with gps feed for accuracy.
Stan

On Thu, 23 Dec 2004 04:44:35 -0800, wrote:

>
>
wrote:
>
>> Most RNAV approaches have the notations:
>>
>> "GPS or RNP - 0.3 required", and
>> "DME/DME RNP - 0.3 not authorized"
>>
>> 1. The "or RNP .3" seems to imply some navigation unit other than gps
>> can have rnp .3 Any idea what?
>
>There is this "fairyland" concept that RNP is sensor independent. This is
>true for large numbers, where INS or IRUs will provide the integrity and
>accuracy required. But, with small values such as RNO 0.3, it is almost
>impossible to satisfy the RNP qualification requirements without GPS as
>the primary sensor.
>
>>
>>
>> 2. If an FMS with rnp .3 is able to conduct this approach, wouldn't
>> it need a gps input to be that accurate? Surely IRS with dme updating
>> can't be used for any non prec approach?
>
>The airline industry conned the FAA to let them use IRUs and DME/DME for a
>couple of years, until some dramatic map shifts almost caused a couple of
>CFIT accidents.
>
>>
>>
>> 2. Any approaches where dme/dme rnp .3 IS authorized?
>>
>
>Only with specials at a few locations with very robust DME reception down
>in the weeds. There are no public procedures.

January 5th 05, 11:50 PM
wrote:
> Thanks Tim and Gene for you insights. I'm told Alaska Airlines has
> rnp .1 approval for some approaches up there. I presume this must be
> IRS (for smoothing) with gps feed for accuracy.
> Stan

Not sure if this helps but the FAA stood up a site from a 2003
conference at:

http://www.faa.gov/arp/aal/2003%20AAL%20Airports%20Conference.cfm

Note the following two presentations are 50+ and 100+ MB respectively,
so d/l-er beware ;)

http://www.faa.gov/arp/aal/2003%20FAA%20AAL%20Airports%20Conference/NAS/NAS.ppt
http://www.faa.gov/arp/aal/2003%20FAA%20AAL%20Airports%20Conference/AVN.ppt
Regards,
Jon

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