Clarification needed on approach procedures

[11thHour]

http://www.naco.faa.gov/d-tpp/0603/00982I6.PDF

This is the ILS RWY 6 for KTTN. My question is this: Lets say the aircraft position is directly over the tower in the lower left part of the plan view. ATC tells the pilot "maintain 3000, turn right heading 090, cleared ILS RWY 6 approach". I understand that since he is being radar vectored, the aircraft is expected to NOT execute the racetrack pattern, but to proceed straight in. But - at which point can the pilot descend to 1900 feet, the mda for gs intercept? Is it within 1 minute of the LOM as long as he's established on the LOC? What is throwing me is this blurb out of AIM 5-4-7(b):

"...the procedure turn of a published IAP shall not be considered a segment of that IAP until the aircraft reaches the inital fix or facility upon which the pt is based."

So, technically is he not established on a published course until he passes the LOM? Or, since he doesn't have to execute a PT because of radar vectors, does this not apply. I'm probably making this more complicated than it is, but if anyone could clarify this for me that would be great.

 

[dhc8fo]

In addition to clearance to execute the approach, you have been given an altitude and heading that you should maintain until you become established on the final approach course (058 is centered on your LOC, or whatever YOUR tolerance is--some are more lax about what defines established--my established is within one dot of course). At that point you can begin a descent to no less than 1900 feet prior to Trenn. In this situation, with everything working and life great, I would ride the glideslope down rather than dive to 1900. I would verify that I am not below that 1900 when I ain't supposed to be though.

 

[Daytonaflyer]

That's correct. Do not descend until you are established on the LOC inbound. If you feel that you are too high, you can always request a descent lower with ATC before you are established inbound, that way you don't have to rush to get down.

 

[midlifeflyer]

http://www.naco.faa.gov/d-tpp/0603/00982I6.PDF

This is the ILS RWY 6 for KTTN. My question is this: Lets say the aircraft position is directly over the tower in the lower left part of the plan view. ATC tells the pilot "maintain 3000, turn right heading 090, cleared ILS RWY 6 approach".

Is that a real clearance or one you made up for the purpose of the question?

I ask because (1) I doubt ATC would bring you over the highest obstacle in the area if it also meant he had to keep you up that high that close to the final approach course and (2) I don't see the words "maintain 3000' until established on the localizer as part of the clearance. I really don't think you would get the clearance you describe.

So, if I actually got that clearance, I would assume there was something wrong with it and ask ATC what the wanted me to do. Heck, If I needed to stay that high, I'd probably ask for the procedure turn as a way of losing altitude.

(Any glideslope gurus who can tell us whether at 3000' at the described intercept, posiiton you would intercept the "real" glideslope?)

 

[dhc8fo]

3. The glide path projection angle is normally adjusted to 3 degrees above horizontal so that it intersects the MM at about 200 feet and the OM at about 1,400 feet above the runway elevation. The glide slope is normally usable to the distance of 10 NM. However, at some locations, the glide slope has been certified for an extended service volume which exceeds 10 NM.

I am no mathematician so I can't speak for altitude of the GS...that is why I say always double check that you aren't lower than you should be for where you are on the approach if you are flying what appears to be a reliable glideslope.

 

[11thHour]

Thanks for the replies. It is a clearance I made up, came up in a discussion with a fellow pilot. I guess I should have been clearer about my question. It's at what point to descend to 1900 feet, the minimum glide slope intercept altitude, off of the vector. I gather from the replies that as soon as I'm established on the LOC I can, but is that true if I'm more than one minute out from the LOM when I intercept the LOC?

 

[void]

A couple points.

1. Your outside the 10 mile ring. Use the MSA. No lower than 2500.

2. I honestly don't think I've seen too many people being vectored around from that direction, and if they are they are typically above that. The reason is that from that position you have PNE's airspace is at 2800 and lower and you are also close to NXX which starts at 2900, and you are right at the border for both class D's. PHL approach would keep you at least 3000, if not higher until closer in, so you do not interfere with the other airports operations.

3. It's also interesting to note that I don't believe that obsticle is even on the Jepp plates for this approach. I think the highest obsticle they show is the one to the northeast. So you wouldn't have even been aware of it had you been looking at jepps.

 

[Tonala2k]

Nothing wrong with the clearance.

*turn Heading 090 maintain 3000'
*Intercept the Loc. and turn on course (I can't believe someone would call them selves established before they have finished a turn on course)
*At 10NM TRENN descend maintain 2000'
*intercept and maintain glide slope. If glide slope dose not cross TRENN at 1809' proceed with LOC IAP.

 

[Amish RakeFight]

1900 when the localizer comes in. If you're being radar vectored and cleared for the approach, a clearance to maintain 3000 will usually be followed by until established which means that once the needle comes in, you can decend down to 1900.