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I ran across a few symbols on the Jepp charts that I don't know about. I tried to find the answers in the legends, but am having a hard time.
In IND, there is an RNAV (GPS) Y Rwy 5L. What is the Y? Then there is an RNAV (RNP) Z Rwy 5L. The charts are basically the same. However, on the Y chart there are three different MDAs, the first is called LPV. What is that? Then on the Z chart it specifies two different MDAs, one is with an RNP of 0.15 and the other is 0.30. I imagine this pertains to equipment that is above my pay scale.
I ran across a few symbols on the Jepp charts that I don't know about. I tried to find the answers in the legends, but am having a hard time.
In IND, there is an RNAV (GPS) Y Rwy 5L. What is the Y? Then there is an RNAV (RNP) Z Rwy 5L. The charts are basically the same. However, on the Y chart there are three different MDAs, the first is called LPV. What is that? Then on the Z chart it specifies two different MDAs, one is with an RNP of 0.15 and the other is 0.30. I imagine this pertains to equipment that is above my pay scale.
Thanks!
1. The "Y" and "Z" are just identifiers for multiple approaches based on the same navigation equipment to the same runway with diffrent procedures.
2. "LPV" = Localizer Precision with Vertical guidance. Under an LPV minimum you would have a "DA" in lieu of an MDA. A LPV is a GPS / RNAV procedure that utliizes a ground based system (WAAS) to get an accurate vertical location of you aircraft in addition to the satellites for the lateral in order to accurately provide a glideslope and track your progress on it based on the data it recieves. You must have a WAAS capable RNAV system on board the aircraft. It would be flown the same as an ILS down to a DA where you would go missed if you didn't have the appropriate environment in sight. Once again, the LPV and LNAV / VNAV systems are not "dive and drive" type MDA approaches. They are flown on a glideslope to a DA just like an ILS, where a missed is required immediately upon reaching DA if the environment is not in sight.
3. "RNP" = Required Navigation Performance. It is the tolerance that the navigation equipment in your aircraft must be cabale of operating within, in order to utilize the procedure. Normally there is an allowance for momentary deviations of no more than 1 times the specified RNP number. RNP .3 would be .3 nm either side of centerline meaning that the aircraft navigation system must be able to maintain that tolerance and alert the pilot if it cannot. For instance, GPS terminal mode is 2 nm either side of course or Approach mode is normally .3 nm either side.
1. The "Y" and "Z" are just identifiers for multiple approaches based on the same navigation equipment to the same runway with diffrent procedures.
2. "LPV" = Localizer Precision with Vertical guidance. Under an LPV minimum you would have a "DA" in lieu of an MDA. A LPV is a GPS / RNAV procedure that utliizes a ground based system (WAAS) to get an accurate vertical location of you aircraft in addition to the satellites for the lateral in order to accurately provide a glideslope and track your progress on it based on the data it recieves. You must have a WAAS capable RNAV system on board the aircraft. It would be flown the same as an ILS down to a DA where you would go missed if you didn't have the appropriate environment in sight. Once again, the LPV and LNAV / VNAV systems are not "dive and drive" type MDA approaches. They are flown on a glideslope to a DA just like an ILS, where a missed is required immediately upon reaching DA if the environment is not in sight.
3. "RNP" = Required Navigation Performance. It is the tolerance that the navigation equipment in your aircraft must be cabale of operating within, in order to utilize the procedure. Normally there is an allowance for momentary deviations of no more than 1 times the specified RNP number. RNP .3 would be .3 nm either side of centerline meaning that the aircraft navigation system must be able to maintain that tolerance and alert the pilot if it cannot. For instance, GPS terminal mode is 2 nm either side of course or Approach mode is normally .3 nm either side.
Thanks for your time in replying. It answers my question perfectly.
1. The "Y" and "Z" are just identifiers for multiple approaches based on the same navigation equipment to the same runway with diffrent procedures.
2. "LPV" = Localizer Precision with Vertical guidance. Under an LPV minimum you would have a "DA" in lieu of an MDA. A LPV is a GPS / RNAV procedure that utliizes a ground based system (WAAS) to get an accurate vertical location of you aircraft in addition to the satellites for the lateral in order to accurately provide a glideslope and track your progress on it based on the data it recieves. You must have a WAAS capable RNAV system on board the aircraft. It would be flown the same as an ILS down to a DA where you would go missed if you didn't have the appropriate environment in sight. Once again, the LPV and LNAV / VNAV systems are not "dive and drive" type MDA approaches. They are flown on a glideslope to a DA just like an ILS, where a missed is required immediately upon reaching DA if the environment is not in sight.
3. "RNP" = Required Navigation Performance. It is the tolerance that the navigation equipment in your aircraft must be cabale of operating within, in order to utilize the procedure. Normally there is an allowance for momentary deviations of no more than 1 times the specified RNP number. RNP .3 would be .3 nm either side of centerline meaning that the aircraft navigation system must be able to maintain that tolerance and alert the pilot if it cannot. For instance, GPS terminal mode is 2 nm either side of course or Approach mode is normally .3 nm either side.
Also, the Z, Y, X etc. go in order of the lowest available minimums for the approaches. Z approaches having the lowest minimums. In the case of the RNAV/GPS/RNP type approaches, the lower minimums will be based on the airborne equipment used. When you see multipule ILS approaches (ie. ILS Z, ILS Y) the different minimums are usually based on missed approach climb gradient.
If the approach is deliniated by a "Z", "Y", etc it is probably a Special aircrew/aircraft certification required approach.
Beyond the standard RNP requirements for an RNAV is the requirement for an FMS system to be able to fly an accurate curved track. I believe this is called Radius to fix or "RTF" capablility.
I great example is an approach to Long Beach with threads the needle between arrival corridors and the Palisades hills.
Professional Pilot magazine did a nice article a couple of months ago about this capability/training requirements.
Watch for the ball note: Special aircrew and aircraft certification required" on these approaches.
If the approach is deliniated by a "Z", "Y", etc it is probably a Special aircrew/aircraft certification required approach.
I'm not sure if that is true or not. I remember looking at various ILS procedures at places like VPS, and others. There is nothing on the plate that says "special aircrew/aircraft certification required". I did see on one that the ONLY difference between the Z and Y plate was the missed approach.
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