Some IFR questions
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Some IFR questions
A few questions about IFR from a novice.
1. If approaching from a direction which happens to be the same as the outbound of a reversal procedure, can you bypass the sector entry and go straight into the reversal then outbound in the approach?
2. Seems to be a moot point on Australian charts nowadays, but if the altitude over the aid/initial approach fix was not underlined as not below this altitude (3000' for example) and your LSALT track or sector MSA brought you inbound at a lower altitude (2600' for example), could you commence the approach at your lower inbound altitude?
3. Now, outbound for the approach it specifies a certain time outbound, lets say 4 minutes. Is it possible for you to shorten this and turn for inbound if there is no DME restriction etc?
4. Established inbound, you've leveled off at MDA, then NAVAID failure or suspect whilst inbound - Initiate a climb immediately to where you dead reckon the aid to be and conduct missed approach procedure?
Thanks in advance, I have my hard hat on.
1. If approaching from a direction which happens to be the same as the outbound of a reversal procedure, can you bypass the sector entry and go straight into the reversal then outbound in the approach?
2. Seems to be a moot point on Australian charts nowadays, but if the altitude over the aid/initial approach fix was not underlined as not below this altitude (3000' for example) and your LSALT track or sector MSA brought you inbound at a lower altitude (2600' for example), could you commence the approach at your lower inbound altitude?
3. Now, outbound for the approach it specifies a certain time outbound, lets say 4 minutes. Is it possible for you to shorten this and turn for inbound if there is no DME restriction etc?
4. Established inbound, you've leveled off at MDA, then NAVAID failure or suspect whilst inbound - Initiate a climb immediately to where you dead reckon the aid to be and conduct missed approach procedure?
Thanks in advance, I have my hard hat on.
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If I understand the questions correctly:
1) Yes.
2) Probably not. You can be at any altitude that any chart or procedure says is safe for your position and track. Your track LSALT is probably only safe up to the aid, so is not useful as soon as you cross over it for the approach. Many Procedures begin from the MSA (whichever is most limiting), so if you are inbound from the side with the lower MSA, once again this is no good for you once you cross the aid and you should be at the higher altitude.
3) Yes, but. You can adjust the timing, however this should normally be for wind. You can't just turn inbound whenever you're good and ready - you're complying with an approach procedure.
4) Spot on.
A word of caution - ppruners may be happy to help and we'll all throw in our two cents, but we're not all experts and I personally haven't been bothered to check my Jepps for these responses. You might get some good basic advice that will point you in the right direction (particularly if you're starting out on CIR and everything is confusing the hell out of you), but you should always refer to and (attempt to) understand you Jepps/AIP for this stuff. DIsclaimer over.
1) Yes.
2) Probably not. You can be at any altitude that any chart or procedure says is safe for your position and track. Your track LSALT is probably only safe up to the aid, so is not useful as soon as you cross over it for the approach. Many Procedures begin from the MSA (whichever is most limiting), so if you are inbound from the side with the lower MSA, once again this is no good for you once you cross the aid and you should be at the higher altitude.
3) Yes, but. You can adjust the timing, however this should normally be for wind. You can't just turn inbound whenever you're good and ready - you're complying with an approach procedure.
4) Spot on.
A word of caution - ppruners may be happy to help and we'll all throw in our two cents, but we're not all experts and I personally haven't been bothered to check my Jepps for these responses. You might get some good basic advice that will point you in the right direction (particularly if you're starting out on CIR and everything is confusing the hell out of you), but you should always refer to and (attempt to) understand you Jepps/AIP for this stuff. DIsclaimer over.
2) What Icarus said is right, however if the MSA is say 5000', your LSALT is 4000' and once you pass over the aid you're able (on the chart) to descend to say 3000' on the outbound leg before becoming established inbound, then I'm not aware on any reason why you couldn't start the approach from a lower altitude. This is of course provided you are at least on a heading to intercept the outbound track once passing overhead the aid. Remember the approach is designed to 'get you visual' with respect for limiting safe altitudes. As long as you are above a published minimum safe altitude at all times then it's ok.
It would then be a question of why or if you should descent to the LSALT prior to starting approach and would be dependent on the variables involved with becoming visual. These would obviously vary with runway in use, the aerodrome itself with respect to the approach and prevailing weather conditions.
It would then be a question of why or if you should descent to the LSALT prior to starting approach and would be dependent on the variables involved with becoming visual. These would obviously vary with runway in use, the aerodrome itself with respect to the approach and prevailing weather conditions.
1 - Yes you can go straight onto the outbound leg of the circling approach as long as your heading is within 30 degrees of the outbound track.
2 - Consider the heights on your chart to be the lowest you can go, in an Approach you don't say drop to 2200 feet at 25 miles upon entering the MSA, if you are flying a turbine your fuel burn is out of control at low altitude, so you want to stay as high as you can for as long as you can. I'm usually at 3000 feet at 10 mile, and will loose height in the sector entry/holding pattern or arc. Preferably i'm at 3000 feet/10 miles on the extended centreline of the the runway approach. Just remember if the inbound leg of an approach has a limiting height, you cannot descend below it until you are within 5 degrees of track.
3 - as Icarus said
4 - Yes, the most sensible thing to do, just don't do anything stupid quickly!
5 - ill second to Icarus's disclaimer
2 - Consider the heights on your chart to be the lowest you can go, in an Approach you don't say drop to 2200 feet at 25 miles upon entering the MSA, if you are flying a turbine your fuel burn is out of control at low altitude, so you want to stay as high as you can for as long as you can. I'm usually at 3000 feet at 10 mile, and will loose height in the sector entry/holding pattern or arc. Preferably i'm at 3000 feet/10 miles on the extended centreline of the the runway approach. Just remember if the inbound leg of an approach has a limiting height, you cannot descend below it until you are within 5 degrees of track.
3 - as Icarus said
4 - Yes, the most sensible thing to do, just don't do anything stupid quickly!
5 - ill second to Icarus's disclaimer
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I didn't get any replies when I posted this last night as part of another thread so I'll try here:
Instrument Technique
Quick edit note: All references are to the plates becoming effective 20 NOV 08.
Hi everybody,
With reference to the Perth RWY 03 ILS/LOC-Y and ILS/LOC-Z approach plates (-Y refers to using the DME from PH ILS and -Z refers to using DME from the IPN LOC) am I correct in assuming that there is no instruction as to which plate to use other than simply to join the 03 ILS? Without an approved GPS they'd have to know that I had more than one DME receiver onboard.
So if an aeroplane is equipped with only one DME receiver (the VOR/ILS) how does the pilot fly the Alice Springs ILS RWY 12 as the only DME I can see is paired with the VOR? (See the lack of a DME listed in the IAS LOC freq box.) How does this relate to the "NAVAID RQ: DME (LOC ONLY)" note at top right?
Also with the Alice Springs approach there is a note:
Quote:
FROM VOR/NDB, INTERCEPT & TRACK LOC 295deg OUTBOUND. 30 SEC AFTER CROSSING GP COMMENCE PROC TURN.
. Assuming that GP is for Glide Path (AIP GEN 2.2); that is a cool procedure!
OK lastly to my problem of intercepting the LOC from a DME Arc at a reasonable DME dist without using the ADF (recently attempting it on MS Flight Sim). Looking at the PH ILS RWY 24 plate if joining from the 10 DME Arc the Lead Radial is 073deg PH (the LOC azimuth is 240 the reverse of which is 060). Flying it in a Baron (PERF CAT B) I tend to either fly right through full scale deflection on the LOC or to turn too early/too sharply that when I finally get to the LOC the GS is well below me (couldn't descend below 2500 so must intercept no closer than 8.6 DME). From my training I remember hearing that the Lead Radial was designed for AC with a much larger turning radius but I can't seem to recall the trick we were taught to get it right.
Cheers,
~FRQ CB
Instrument Technique
Quick edit note: All references are to the plates becoming effective 20 NOV 08.
Hi everybody,
With reference to the Perth RWY 03 ILS/LOC-Y and ILS/LOC-Z approach plates (-Y refers to using the DME from PH ILS and -Z refers to using DME from the IPN LOC) am I correct in assuming that there is no instruction as to which plate to use other than simply to join the 03 ILS? Without an approved GPS they'd have to know that I had more than one DME receiver onboard.
So if an aeroplane is equipped with only one DME receiver (the VOR/ILS) how does the pilot fly the Alice Springs ILS RWY 12 as the only DME I can see is paired with the VOR? (See the lack of a DME listed in the IAS LOC freq box.) How does this relate to the "NAVAID RQ: DME (LOC ONLY)" note at top right?
Also with the Alice Springs approach there is a note:
Quote:
FROM VOR/NDB, INTERCEPT & TRACK LOC 295deg OUTBOUND. 30 SEC AFTER CROSSING GP COMMENCE PROC TURN.
. Assuming that GP is for Glide Path (AIP GEN 2.2); that is a cool procedure!
OK lastly to my problem of intercepting the LOC from a DME Arc at a reasonable DME dist without using the ADF (recently attempting it on MS Flight Sim). Looking at the PH ILS RWY 24 plate if joining from the 10 DME Arc the Lead Radial is 073deg PH (the LOC azimuth is 240 the reverse of which is 060). Flying it in a Baron (PERF CAT B) I tend to either fly right through full scale deflection on the LOC or to turn too early/too sharply that when I finally get to the LOC the GS is well below me (couldn't descend below 2500 so must intercept no closer than 8.6 DME). From my training I remember hearing that the Lead Radial was designed for AC with a much larger turning radius but I can't seem to recall the trick we were taught to get it right.
Cheers,
~FRQ CB
The Green Goblin
I think he's asking from a legal perspective, not a practical one. Legally there is no reason why you can't do it, provided you're able to go straight outbound in the approach. If a holding pattern or sector entry is required, then it becomes the limiting height published for the holding pattern. Practically it may not be worth your while, however if the cloud base is reported between the MSA and your LSALT, then why wouldn't you descend to your LSALT to remove the need to do the approach? No one is saying do it right at 25nm, but you can plan that as your descent altitude. If fuel is that critical then there's something wrong with your fuel planning.
Legals aside, from a practical perspective - there are way too many variables to consider.
I think he's asking from a legal perspective, not a practical one. Legally there is no reason why you can't do it, provided you're able to go straight outbound in the approach. If a holding pattern or sector entry is required, then it becomes the limiting height published for the holding pattern. Practically it may not be worth your while, however if the cloud base is reported between the MSA and your LSALT, then why wouldn't you descend to your LSALT to remove the need to do the approach? No one is saying do it right at 25nm, but you can plan that as your descent altitude. If fuel is that critical then there's something wrong with your fuel planning.
Legals aside, from a practical perspective - there are way too many variables to consider.
In a cat B a/c tune NAV 1 to the ILS, and NAV 2 to the VOR frequency. When VOR 2 is half a scale off the track (5 degree), start the turn and you should be lined up on the LLZ when rolling wings level. In a BE58 lower approach flap on the arc (approx 10 track miles to touchdown) reduce power to 16inches when on slope to initiate a ROD 5 x groundspeed, Lower Gear at 5 mile landing flap at 1 mile/300 feet visual or if in IMC leave retracted until DH where you commence your missed approach.
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Doesn't anyone have DME hold?
I've never flown an IFR aircraft with a DME that didn't have a "Hold" function - have I been spoiled?
For mine, the only reason an additional Nav receiver or GPS comes into this ILS question is meeting requirements for Special Alternate minima (you can't use GPS to meet the distance requirement if it is a ILS/DME as this would require the pilot to code the DME location, as opposed to referencing the VOR as and aid).
Other than that, you just need to make sure that you "hold" the DME at the right time according to the approach chart you are using.
For mine, the only reason an additional Nav receiver or GPS comes into this ILS question is meeting requirements for Special Alternate minima (you can't use GPS to meet the distance requirement if it is a ILS/DME as this would require the pilot to code the DME location, as opposed to referencing the VOR as and aid).
Other than that, you just need to make sure that you "hold" the DME at the right time according to the approach chart you are using.
I've never flown an IFR aircraft with a DME that didn't have a "Hold" function
Dr
Last edited by ForkTailedDrKiller; 10th Nov 2008 at 05:04.
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So I have been spoiled after all!
Dr - I'm not sure you will gain any sympathy round these parts. Everyone on Pprune knows you're up to 67 GPS and counting!
ad-astra -can you put the GPS distance somewhere in the primary FOV then? My beast has 4 DME displays for each pilot, but if you want a GPS distance to anything but the active WP then it's going to be down on the FMS screen.
Dr - I'm not sure you will gain any sympathy round these parts. Everyone on Pprune knows you're up to 67 GPS and counting!
ad-astra -can you put the GPS distance somewhere in the primary FOV then? My beast has 4 DME displays for each pilot, but if you want a GPS distance to anything but the active WP then it's going to be down on the FMS screen.
Everyone on PPRuNe knows you're up to 67 GPS and counting!
For the record I am currently stable at 5 in the aeroplane (Garmin 430W in the panel; 496 and LS800 tablet with GPS on the yoke; III Pilot in the flight bag; plus one in the PLB)
not to forget "Helga the Swedish backpacker" talking cigarette lighter/co-pilot
Dr
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4. Established inbound, you've leveled off at MDA, then NAVAID failure or suspect whilst inbound - Initiate a climb immediately to where you dead reckon the aid to be and conduct missed approach procedure?
Without my plates at hand, I can think of two where it isn't so: Mareeba VOR Approach and Cooktown NDB Approach. Once at the MDA, DR tracking to either of these aids after a failure could easily be fatal.
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Mr Boeings "finest product" (737NG) does not have the luxury of a DME hold.
Ahh yes this is true, but you can drop any position from the fix page (such as a range distance/bearing that crosses your current leg) into the legs page and create a waypoint as simple as click click.
Then you can do what you like with it regarding holding or VNAV profile.
You can also easily build an approach thats not in the data base by creating waypoints (using place/bearing/distance) quite easily too.
Although the 737's FMC has its limits, its very user friendly if you know how to use it
Ahh yes this is true, but you can drop any position from the fix page (such as a range distance/bearing that crosses your current leg) into the legs page and create a waypoint as simple as click click.
Then you can do what you like with it regarding holding or VNAV profile.
You can also easily build an approach thats not in the data base by creating waypoints (using place/bearing/distance) quite easily too.
Although the 737's FMC has its limits, its very user friendly if you know how to use it
