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15 votes
Accepted

Why is training regarding the loss of RAIM given so much more emphasis than training regarding the loss of SBAS?

From a safety perspective RAIM is more critical than SBAS. If you are flying using GPS, you always rely on RAIM to keep you safe, sometimes you need SBAS too. Receiver Autonomous Integrity Monitor is ...
DeltaLima's user avatar
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11 votes
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What is "required navigation performance" or "RNP"?

RNP (Required Navigation Performance) is a standard which avionics manufacturers may choose to design/certify their products for. It guarantees a particular level of navigation performance that ...
Lnafziger's user avatar
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10 votes

Does RNAV and RNP specify what type of longitudinal accuracy the system has?

It does, but it's a different issue than just positional accuracy. The goal of RNAV is to keep the aircraft within the confines of the specified airspace. Longitudinally, you will always be within the ...
Gerry's user avatar
  • 19.7k
9 votes

Why is training regarding the loss of RAIM given so much more emphasis than training regarding the loss of SBAS?

The RAIM (Receiver autonomous integrity monitoring) is what allows you to fly using a GPS. If you lose RAIM, by regulations you cannot use the GPS to navigate. So, it should not be a surprise for you ...
Anas Maaz's user avatar
  • 1,953
9 votes

Why is VNAV and LNAV being prohibited with QFE?

When you set your altimeter to the airport or runway QFE value, the altimeter shows your altitude above the airport or runway threshold: (source: SKYbrary - Altimeter Pressure Settings) The altitude ...
Bianfable's user avatar
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8 votes
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What RNP level is required for an RNP approach if the chart does not specify a value?

RNP approaches require a minimum value of 0.30, be it LNAV only, LNAV/ VNAV or RNP AR. Most of the approaches around the globe are RNP approaches. So, they do not put in the value because it remains ...
Anas Maaz's user avatar
  • 1,953
7 votes
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Can crews hand-fly an RNP AR approach in IMC?

Each operator can impose their own requirements that are at least as strict as what the FAA requires, and these tend to be more strict. For instance, one operator I'm familiar with requires both INS'...
Ralph J's user avatar
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5 votes
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Is baro-VNAV the only possible source of vertical guidance on LNAV/VNAV approach?

I believe @busdriver may have overlooked something. Your TSO 145 or 146 avionics will "fail down" from LPV (a more constrained lateral and lower minima approach) to LNAV/VNAV (wider ...
Catapult's user avatar
4 votes

Does RNAV and RNP specify what type of longitudinal accuracy the system has?

Unfortunately in the US many of the regulations are written to make it difficult to separate accuracy/integrity in the along-track direction from the cross-track direction. DO-229D claims this is &...
Cody P's user avatar
  • 6,775
3 votes

Is baro-VNAV the only possible source of vertical guidance on LNAV/VNAV approach?

Yes. While APV Baro-VNAV and APV SBAS share similar lateral design criteria, the vertical obstacle clearance surfaces are different. In APV Baro-VNAV procedure design is based on barometric reference ...
busdriver's user avatar
  • 3,270
2 votes

The meaning of RNP

Don't take the technical terms too seriously. Technical terms are often poor description of the item, and technical terms in English tend to be particularly bad. These ones are fairly good for the ...
Jan Hudec's user avatar
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2 votes
Accepted

Why are SBAS-equipped planes exempt from the preflight prediction check?

The slide refers to ADS-B integrity, which requires a different integrity level than RNP. The ADS-B preflight check they refer to is a different than the check for RNP. The FAA requires an integrity ...
DeltaLima's user avatar
  • 83.1k
2 votes

What RNP level is required for an RNP approach if the chart does not specify a value?

All those approaches require RNP APCH capability, i.e. a precision of 0.3 on the final segment (see table 1 under GM1 SPA.PBN.100 of Annex V Specific approvals via easa.europa.eu): They also have a ...
assylias's user avatar
  • 1,445
2 votes

Which Navigation Specifications support an RF leg?

First is understanding the difference between RNAV and RNP. This related question: What is the difference between RNAV and RNP? provides a basic answer to that part of your question. To your ...
Gerry's user avatar
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1 vote
Accepted

How is RNP's onboard performance monitoring and alerting system represented in the cockpit?

In Airbuses logic is exactly like described by @RalphJ on 737. REQUIRED navigation performance (RNP) is determined by flight management system based on phase of flight or type of approach being flown. ...
busdriver's user avatar
  • 3,270
1 vote

How is RNP's onboard performance monitoring and alerting system represented in the cockpit?

On the 737 NG and Max the ANP (actual navigation performance) and the RNP (required navigation performance) are shown at the bottom center of the Navigation Display: Source: http://www.b737.org.uk/...
Ralph J's user avatar
  • 51.1k
1 vote

Why are the altitudes on an RNP IAC shown on the point while for a conventional approach are parallel to the route? Is there an actual difference?

This is merely a difference between charting styles from old to new. This happens when a country changes their style which only affects newer procedures. The VOR RWY 27 was last updated in 2016: The ...
Timbo's user avatar
  • 379
1 vote

Which airspace requires what RNP?

For completeness, Please refer to the following website: https://www.uasc.com/docs/default-source/documents/whitepapers/uasc_rnp-rnav_whitepaper.pdf Here are some extracts that allow to compare US ...
user40476's user avatar
  • 1,772
1 vote

What is the correlation between RNP level and the CDI indication?

The CDI shows how far you are from where the navigator thinks you should be. RNP refers to how wrong the navigator itself is allowed to be. ANP is how wrong it thinks it may be at any given moment, ...
StephenS's user avatar
  • 27.7k
1 vote

What is the correlation between RNP level and the CDI indication?

The Performance Based Navigation concept allows to optimize the instrument procedure design with the aircraft navigation performance. This concept is used en route, to reduce aircraft separation, and ...
user40476's user avatar
  • 1,772

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