If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
DME req'd on ILS (not ILS-DME) approach?
Hi folks. I've got a bit of a puzzle here.
First off, I'm a student pilot, so maybe I haven't gotten to this yet. Take a look at the ILS 18 plate for Springdale, AR (ASG): http://myairplane.com/databases/appr...l/ASG_ir18.pdf First, note that the approach is "ILS RWY 18" --- Next, read in the notes section: Circling NA east of Rwy 18-36, inoperative table does not apply. DME from RZC VORTAC Simultaneous reception of I-ASG and RZC DME required. --- So, the way I read this, DME is not required, since the approach is ILS not ILS DME, but it is required since "simultaneous reception ... is required." I guess my real question is, "Is this approach authorized for an aircraft without DME? And if not, why don't they call it ILS-DME?" but read on for my thinking... Looking at the chart, here are the uses of DME that I see: 1. DME arcs to intercept the localizer 2. A 3.8 DME non-precision MAP (my Jepp plate shows a non-precision decent with DME 3.8 as the MAP) 3. WESTY intersection, 18 DME out, which can also be identified by a cross-radial from the DAK VOR. Now, this is how I reason (i.e. rationalize. my way out of these: 1. I tune the RZC VORTAC and fly the DME ARC, but once I turn to intercept the localizer, I no longer care about the ARC, so I don't need DME anymore. 2. DME would be helpful here, and simultaneous reception would be required, but I could also time from the FAF to identify the MAP. 3. I can swap VOR receivers once safely established on missed approach, so I shouldn't need this for the inbound part of the approach. To my thinking, #2 is the shakiest logic. Still, if DME is required, why don't they just call it an ILS-DME approach? -- Don Faulkner, KB5WPM | (This space | "All that is gold does not glitter." unintentionally | "Not all those who wander are lost." left blank) | -- J.R.R. Tolkien |
#2
|
|||
|
|||
"Don Faulkner" wrote in message news Hi folks. I've got a bit of a puzzle here. First off, I'm a student pilot, so maybe I haven't gotten to this yet. Take a look at the ILS 18 plate for Springdale, AR (ASG): http://myairplane.com/databases/appr...l/ASG_ir18.pdf First, note that the approach is "ILS RWY 18" --- Next, read in the notes section: Circling NA east of Rwy 18-36, inoperative table does not apply. DME from RZC VORTAC Simultaneous reception of I-ASG and RZC DME required. --- So, the way I read this, DME is not required, since the approach is ILS not ILS DME, but it is required since "simultaneous reception ... is required." I guess my real question is, "Is this approach authorized for an aircraft without DME? And if not, why don't they call it ILS-DME?" but read on for my thinking... Looking at the chart, here are the uses of DME that I see: 1. DME arcs to intercept the localizer 2. A 3.8 DME non-precision MAP (my Jepp plate shows a non-precision decent with DME 3.8 as the MAP) 3. WESTY intersection, 18 DME out, which can also be identified by a cross-radial from the DAK VOR. Now, this is how I reason (i.e. rationalize. my way out of these: 1. I tune the RZC VORTAC and fly the DME ARC, but once I turn to intercept the localizer, I no longer care about the ARC, so I don't need DME anymore. 2. DME would be helpful here, and simultaneous reception would be required, but I could also time from the FAF to identify the MAP. 3. I can swap VOR receivers once safely established on missed approach, so I shouldn't need this for the inbound part of the approach. To my thinking, #2 is the shakiest logic. Still, if DME is required, why don't they just call it an ILS-DME approach? Looks to me like the only portion of this approach that requires DME is the 8 DME arc to the localizer. If you're going to fly this procedure you must be able to receive the localizer and DME from RZC VORTAC simultaneously. To fly it without simultaneous reception would require you to tune and identify the localizer upon reaching one of the lead radials. Not an impossible task, but one that can be rather distracting and possibly vertigo-inducing. I have an old chart book with a previous version of this approach, Amdt 6A, that does not have this simultaneous reception requirement. It appears somebody thought it was a good thing to add. There are a couple of curious things about this approach. What is the purpose of TINSE and how does one identify it? I looked up TINSE in the Location Identifiers book, it's 8 DME from RZC on the localizer, but you couldn't tell that from the plate. What is the purpose of "2800 NoPT (7.5)" just inside of the arc? I see only three ways to get to that point once inbound on the localizer; via the arc which is already designated NoPT, via radar vectors which by regulation prohibit a PT, or after already having completed a PT. |
#3
|
|||
|
|||
"Steven P. McNicoll" wrote in message link.net... There are a couple of curious things about this approach. What is the purpose of TINSE and how does one identify it? It's certainly odd, isn't it. I thought it was some "vectors to final" crutch to appease the GPS crowd. |
#4
|
|||
|
|||
DME is not required to fly this procedure unless you elect to fly the ARC
initial approach segments. In that case, you have to be able to receive the DME from the VOR at the same time you are receiving the LOC. It is a boilerplate note they put on anytime the DME is not frequency-paired with the ILS. But, you're right, you could easily fly the ARC, then use the lead radials to change to the LOC. The note serves no real purpose on this IAP. Don Faulkner wrote: Hi folks. I've got a bit of a puzzle here. First off, I'm a student pilot, so maybe I haven't gotten to this yet. Take a look at the ILS 18 plate for Springdale, AR (ASG): http://myairplane.com/databases/appr...l/ASG_ir18.pdf First, note that the approach is "ILS RWY 18" --- Next, read in the notes section: Circling NA east of Rwy 18-36, inoperative table does not apply. DME from RZC VORTAC Simultaneous reception of I-ASG and RZC DME required. --- So, the way I read this, DME is not required, since the approach is ILS not ILS DME, but it is required since "simultaneous reception ... is required." I guess my real question is, "Is this approach authorized for an aircraft without DME? And if not, why don't they call it ILS-DME?" but read on for my thinking... Looking at the chart, here are the uses of DME that I see: 1. DME arcs to intercept the localizer 2. A 3.8 DME non-precision MAP (my Jepp plate shows a non-precision decent with DME 3.8 as the MAP) 3. WESTY intersection, 18 DME out, which can also be identified by a cross-radial from the DAK VOR. Now, this is how I reason (i.e. rationalize. my way out of these: 1. I tune the RZC VORTAC and fly the DME ARC, but once I turn to intercept the localizer, I no longer care about the ARC, so I don't need DME anymore. 2. DME would be helpful here, and simultaneous reception would be required, but I could also time from the FAF to identify the MAP. 3. I can swap VOR receivers once safely established on missed approach, so I shouldn't need this for the inbound part of the approach. To my thinking, #2 is the shakiest logic. Still, if DME is required, why don't they just call it an ILS-DME approach? -- Don Faulkner, KB5WPM | (This space | "All that is gold does not glitter." unintentionally | "Not all those who wander are lost." left blank) | -- J.R.R. Tolkien |
#5
|
|||
|
|||
The following is the paragraph (807) out of FAA Handbook 8260.19C, "Flight
Procedures and Airspace" that resulted in that reception note even though it makes no sense at this particular location: 3) DME frequencies are paired with the frequencies of the VOR, localizer, or MLS. When a non-paired DME is used in a VOR/DME, ILS/DME, etc., procedure, simultaneous reception of both facilities must be assured. This requires a standard Note indicating the DME location and the identification of both facilities: "DME from XYZ VORTAC. Simultaneous reception of I-ABC and XYZ DME required:" DME frequencies are not paired with NDBs; and, DME antennas may or may not be collocated with the NDB. For NDB/DME SIAPs, use standard Note: "Simultaneous reception of ABC NDB and XYZ DME required." |
#6
|
|||
|
|||
It is a boilerplate note they put on anytime the DME is not
frequency-paired with the ILS. There are zillions of arcs to localizers that don't have this note. The 8260.19C says they only apply to approaches with DME in the title. I have an old plate for this approach, and it lacks the note. But, you're right, you could easily fly the ARC, then use the lead radials to change to the LOC. That is precisely the purpose of the lead radials, is it not? |
#7
|
|||
|
|||
On Thu, 02 Oct 2003 10:47:47 -0500, Don Faulkner
wrote: Hi folks. I've got a bit of a puzzle here. First off, I'm a student pilot, so maybe I haven't gotten to this yet. Take a look at the ILS 18 plate for Springdale, AR (ASG): http://myairplane.com/databases/appr...l/ASG_ir18.pdf First, note that the approach is "ILS RWY 18" --- Next, read in the notes section: Circling NA east of Rwy 18-36, inoperative table does not apply. DME from RZC VORTAC Simultaneous reception of I-ASG and RZC DME required. --- So, the way I read this, DME is not required, since the approach is ILS not ILS DME, but it is required since "simultaneous reception ... is required." I guess my real question is, "Is this approach authorized for an aircraft without DME? And if not, why don't they call it ILS-DME?" but read on for my thinking... Under the approach naming conventions used by TERPS, DME only appears in the approach name if it is required in order to fly the FINAL approach segment. "ILS procedures do not require DME to fly the final approach, even if a DME fix has been substituted for one of the marker beacons, therefore, ILS procedures shall not be named ILS/DME. If a procedure requires DME to fly the final approach, the suffix “DME” shall be added; ..." And my interpretation of the note is that, indeed, DME is legally required to fly the approach. It is used to ID two of the IAF's and could be used to ID the MAP (for the LOC approach) and/or Westy (it's not necessary for either one). And yes, you could fly the approach without DME by navigating to NOBBY as the IAF; and using timing if you are using the LOC approach; and using radials to ID WESTY. I don't know the requirements for putting a DME required note in the procedure, when it is possible to fly at least one of the charted procedures without using DME. Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA) |
#8
|
|||
|
|||
"Ron Rosenfeld" wrote in message ... And my interpretation of the note is that, indeed, DME is legally required to fly the approach. It is used to ID two of the IAF's and could be used to ID the MAP (for the LOC approach) and/or Westy (it's not necessary for either one). And yes, you could fly the approach without DME by navigating to NOBBY as the IAF; and using timing if you are using the LOC approach; and using radials to ID WESTY. I don't know the requirements for putting a DME required note in the procedure, when it is possible to fly at least one of the charted procedures without using DME. You're saying this approach can be flown without DME yet you believe DME is legally required to fly this approach? |
#9
|
|||
|
|||
"Steven P. McNicoll" wrote:
You're saying this approach can be flown without DME yet you believe DME is legally required to fly this approach? Is that so unusual? The ILS into CXY used to have ADF REQUIRED on the plate, even though you could easily fly it without such equipment if receiving radar vectors. (The plate now says ADF or RADAR, but was only changed recently.) -- Mike Granby, PP-ASEL,IA Warrior N44578 http://www.mikeg.net/plane |
#10
|
|||
|
|||
Greg Esres wrote: It is a boilerplate note they put on anytime the DME is not frequency-paired with the ILS. There are zillions of arcs to localizers that don't have this note. The 8260.19C says they only apply to approaches with DME in the title. I have an old plate for this approach, and it lacks the note. Guess that shows I am not much better than the person who designed the latest amendment to this IAP, not to mention his/her supervisor and QC staff. ;-) But, you're right, you could easily fly the ARC, then use the lead radials to change to the LOC. That is precisely the purpose of the lead radials, is it not? I hesitate to say "precisely," but, yes, lead radials are for turn anticpation. |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
The perfect approach | Capt.Doug | Home Built | 25 | December 3rd 04 03:37 AM |
Established on the approach - Checkride question | endre | Instrument Flight Rules | 59 | October 6th 03 04:36 PM |
Terminology of New WAAS, VNAV, LPV approach types | Tarver Engineering | Instrument Flight Rules | 2 | August 5th 03 03:50 AM |
IR checkride story! | Guy Elden Jr. | Instrument Flight Rules | 16 | August 1st 03 09:03 PM |
CAT II Minimums on a CAT I Approach | Giwi | Instrument Flight Rules | 11 | July 24th 03 07:46 AM |