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14

There's an FAA paper on RNAV approaches that explains the differences between LP, LPV, LNAV and LNAV/RNAV approaches. I made a table for my own reference but since StackExchange doesn't allow tables (AFAIK) here's a summary: LP: no vertical guidance; WAAS required; MDA for minimums LPV: vertical guidance; WAAS required; DA for minimums LNAV: no vertical ...


12

JERIT is the FAF for the LOC approach, as indicated by the Maltese cross. However, the FAF for the ILS approach is not JERIT; it is the Glide Slope Intercept Point (at 2000 ft indicated altitude) shown by the lightning bolt symbol, which in this particular approach happens to be at the same location as published for JERIT. Keep in mind, however, that the ...


10

LNAV/VNAV approaches were originally designed for larger, more sophisticated turbine aircraft utilizing onboard Flight Management Systems (FMS). These types of approaches uses barometric altimeters and ground radio equipment to compute a descent path and add vertical guidance to an existing non-precision approach. An LPV approach still provides vertical ...


7

In the US, the FAA has done this alot, as in their long term plan to phase out a lot of the VORs. Doing that, they're preemptively just adding a Fix for procedures on top of the VOR so they don't have to update all the procedures when the VOR is decommissioned.


7

RNAV freed aircraft from the airways that were already in place that may have zig zagged from VOR to VOR, but with the limitations of the ATC system based on human controllers, it is still desirable to keep most aircraft on a "road network" so to speak to make it easy to manage separation, so RNAV airways were created between major centers that provide ...


7

LPV is a higher precision approach requiring equipment beyond what is needed for LNAV/VNAV. In particular you need dual WAAS recievers in a certified installation. The improved guidance is what allows the lower DH. See this link for more information.


7

RNP is a numerical value that refers to the level of performance required for a specific published procedure. If the procedure has an RNP 10, then the on-board navigation equipment must be able to calculate its position to within 10 nautical miles. If the procedure has an RNP 0.3, than the equipment must be able to calculate its position to .3nm. ANP is ...


6

You are confusing some terminology. RNAV (GPS) approaches can have several different sets of minima. See the example RNAV (GPS) Y 28L at O'Hare: It has: LPV LNAV/VNAV LNAV sets of minima. LPV is an instrument approach procedure (IAP) with localizer-type precision and with vertical guidance, (hence the name LPV), provides a pilot with a "ILS-style" ...


6

As egid pointed out, pilots typically do not file a specific approach as part of their flight plan. ATC will decide what runways and approaches are in use based on the weather. As the pilots are on their descent to the destination, they will be told which approach to expect. Pilots can always request something different but ATC is trying to get everyone to ...


5

No. The FMS does not use rhumb lines. All RNP/RNAV flight path legs are geodesics. The only exceptions are RF legs (a constant radius circular path about a turn center) and hold legs (a closed racetrack pattern). To quote RTCA DO-236C, Minimum Aviation System Performance Standards: Required Navigation Performance for Area Navigation: RNP Routes and ...


5

In ICAO DOC 9905 (Required Navigation Performance Authorization Required Procedure Design Manual) you can find the following definition in Chapter 2.1 RNP APCH versus RNP AR APCH 2.1.1 RNP APCH is defined as an RNP approach procedure that requires a lateral TSE of +/-1 NM in the initial, intermediate and missed approach segments (MAS) and a lateral ...


5

First of all, an RNP 1 procedure requires a GPS/ GNSS. And as you have said, it requires an inbuilt navigation monitoring and an alerting system. On the other hand, an RNAV 1 procedure does not. In RNAV 1 you can get navigational aid from the IRS/ VOR/ DME or IRS/ DME/ DME. The SIDs and STARs can either be RNAV 1 or RNP 1. RNAV 1 is the system introduced at ...


5

Short answer: there seems to be no general plan to replace airways with Q and T routes. The FAA originally proposed replacing them, but the final rule doesn't include it. You can review the source rulemaking documents in the Federal Register and it looks like the idea of replacing (or retaining) airways seems to have been discarded, possibly in response to ...


5

A conventional hold based on legacy radio-navigation required overflying the hold fix on entry as guidance is only available inbound to the fix and your exact position is known at the fix (with some allowance when inbound if there's a DME at the holding fix.) Hold entries from the holding side of the inbound leg will result in crossing to the non-holding ...


4

FAA Order 8260.46F - Departure Procedure (DP) Program describes "... the policy, guidance, and standardization for initiating, developing, processing, and managing the Departure Procedure (DP) Program." Your questions are broad-based, but Order 8260.46F should provide the answers you are looking for. Here are two figures from Order 8260.46F. These ...


4

A VNAV with localiser approach is normally a backup to a regular ILS should there be a glide slope unserviceability. The use of VNAV to manage the vertical portion of the approach would allow the use of APV minima which are normally lower than using a vertical speed mode. VNAV is a better mode when conducting non-precision approaches as the aircraft is ...


4

The approach above appears to be associated with the Antonio Marino Airport, Colombia, South America: (I don't know if it is current or proposed) Descent below the published DA/H is not permitted due to obstacle clearance requirements. Therefore, a "height loss" (amount of altitude expected to be lost during a go-around [missed approach]) is added to the ...


4

The gist of your question is whether it is possible to couple RNAV with ILS? The following ILS chart of Cochin Airport (VOCI) is an ILS approach where Initial and Intermediate approach are executed using RNAV (GNSS)instead of conventional Navaids but final approach is ILS. Aircraft with RNAV1 capability can execute this approach.


4

The true position of an aircraft in flight can be measured, but the accuracy of any measurement is limited. The actual measured position is the actual true position plus the actual measurement error. Each error of position measurement is 3dimensional. If observed over a long time, the distribution of the errors will have a shape and size that is ...


4

Beginning 2NM prior to reaching the final approach fix of an activated approach, the GPS will smoothly taper down the CDI scale from 1-NM full-scale deflection (from the center) to 0.3-NM at full-deflection over that 2-NM flight distance and reach a scale of 0.3-NM as the final approach fix is reached. AIM Page 1-1-25 "When within 2 NM of the Final ...


3

RNAV(GPS) procedures being combined with LPV or LNAV/VNAV, which are Landing Systems Your confusion here is that LPV is a landing system which it is not. It is a way of saying your GPS is going to work kind of like an ILS and will have similar horizontal/vertical responses on your way down or as the FAA puts it Localizer Performance with Vertical ...


3

Since "radar" means "ATC radar", I'm not sure how a pilot could substitute anything for it. The issue isn't that the pilot needs radar to navigate the approach; it's that's ATC needs radar in order to allow the approach in the first place. Per this answer, ATC can only clear aircraft for an RNAV approach without an IAF if radar monitoring is available. I ...


3

The FAA website predicts pre-flight whether RAIM will be available The RAIM algorithm will tell you during your flight if GPS is working correctly. The pre-flight FAA website check is not a substitute for the use of the RAIM function during flight. It will only show whether the RAIM function is available during flight. RAIM stands for Receiver ...


3

. A LPV approach can provide WAAS vertical guidance as low as 200 feet AGL. LNAV/VNAV approaches also provide approved vertical guidance and existed before the WAAS system was certified. At that time, only aircraft equipped with a flight management system (FMS) and certified baro-VNAV systems could use the LNAV/VNAV minimums. Also the design of an LPV ...


3

Sensors From ICAO Doc 9613: 2.2.1.3 RNAV 5 operations are based on the use of RNAV equipment which automatically determines the aircraft position in the horizontal plane using input from one or a combination of the following types of position sensors, together with the means to establish and follow a desired path: a) VOR/DME; b) DME/DME; c) INS or IRS; and ...


3

You asked the question in terms of ARINC 424 which imposes the constraints of the database structure and use. So I'll try to explain SIDs within that constraint and in the broader sense. The reason for that is that ARINC 424 exists to support the use of an FMS (or an RNAV navigator). But some SIDs don't require an FMS to fly them. The ones that start with "...


3

The answer, broadly is no, handheld GPS units can not be used for IFR RNAV routes (or approaches for that matter). To know if a specific GPS unit is legal for IFR navigation you need to check up on a variety of paperwork, thats covered in this answer. Strictly speaking if you could find a certified unit it would be legal but there are no current units (to my ...


3

If you are above all the published altitudes for pre-FAF fixes you can intercept the GS but you must remain above the published minimum altitudes as apposed to remaining on glide slope. Approaches may also have defined intercept altitudes for the glide slope. This article explains why quite nicely; What this means to pilots is that on some approaches, ...


2

You are partially correct, first of all they are called "RNAV routes" not "RNAV airways" and yes the entire point of RNAV was not needing to fly along a suboptimal preset path but that was because of the fact that you flight plan had you flying directly over the navigational beacons. Like this: RNAV routes allow more efficient flight by connecting random ...


2

Yes, a SID can have three parts as you described. The runway transition defines the path from each runway to get to the common route section of the SID. All runways then share the common route section. After the common route, there may be multiple enroute transtions to get an aircraft on to the rest of its flight plan. Below is the EPKEE RNAV departure from ...


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