Jump to content

Archived

This topic is now archived and is closed to further replies.

Guest alex_m

KBOS Approach

Recommended Posts

Guest j-mo

RC 4.3 in use during a flight from LFPG to KBOS, SCUPP3 STAR for rwy 4R, which is vectors after SCUPP intersection. RC vectors me laterally OK, but only clears me down to 3,000 AGL, which is above the GS. When I am turned over to tower, final instruction is to descend to 2,500 feet, and I have to really hustle the AP (PMDG 747-400X) to get below the GS.I flew this flight two times. The first time, my airplane was a little wonky (e.g. the ND was rotated 90-degrees in map mode during takeoff and approach). So I flew this flight a second time to see if maybe the aircraft's behavior was a factor.I just finished the second flight, and the approach vectors were identical: I was at 3000, above GS when cleared to 2,500, necessitating a pretty steep 'dip' to get under GS.So, what I'm, wondering is:1. Is this the RW approach vector sequence regarding descent clearances?2. If the answer is 'yes', then I must be missing something, so advice would be welcome.3. I realize there are about one bazillion great components in RC, so some anomalies are expected. If this is one, perhaps it could be addressed in the next version.This is FSX and Vista 32, default airports, and I realize that I can request either a visual or IAP to get around this.Thanks one more time for an outstanding product!Regards,

Share this post


Link to post
Share on other sites

The expected crossing height at SCUPP is 11,000. The intersect points for 4R are WINNI at 4,000 and NABBO at 3,000. NABBO is 11.9 nm out loc dme. In your FMC as guidance on the KBOS ARR choose ILS 4R so you can see these in your ND. Getting down from 11,000 to 3,000 in 30 nm should not be a problem. If you want to fly lower use the NOTAMS option on the approach. You'll still get vectors but can deviate from the ATC altitudes given.

Share this post


Link to post
Share on other sites
Guest j-mo

Hi, Ron-Thanks for your reply.Yes, I chose ILS 4R in the FMC, and saw WINNI and NABBO on the ND. I know now (from experience) that I'll be above GS, so I can choose NOTAMS. Is there some way I could have known in advance that I would have needed to do this? I guess what I'm asking is, how frequently does this occur? I know from reading the forum here that if I fly into airports near elevated terrain that I should use NOTAMS. I just didn't anticipate this with KBOS. Is this an option I should utilize as a more or less standard practice? I'm just trying to fine-tune how I use RC.Thanks, and regards,

Share this post


Link to post
Share on other sites

KBOS is just about sea level with an MSA centered on the BO beacon of 2000 to the east and 2500 to the west. From SCUPP 4R might get you a right preferred (or left) down wind in ATC vectors that should carry you far out enough to turn base and then intersect the localizer at about 10 nm out (NABBO) at 3000 where the GS is above you unless you requested a short final. The FAF is 1723 at 5 nm out from the threshold at 6.9 DME from I-BOS. Many people complain that RC vectors them on a base too far out and they sometimes intersect at fifteen out.I'd slow down an airliner to about 180 before exiting downwind and make sure I'm at 3000 with flaps to support that speed and by the time I get to NABBO be at Vflaps one or two notches above landing flaps with full landing configuration by MILT at Vflapslanding with gear down. The slower speeds with flaps give you a better descent profile with some engine power to allow for better spool up should a go-around be required.There is also the potential in FS to give you a false localizer and GS in situations such as 4R at KBOS. Notice that 4R and 22L share the same localizer frequency. In FS both are active with back courses by default. Unless you are within two degrees of centerline you could be reading the wrong ILS. You need to insure the ident is correct (I-BOS in this case) before you engage LOC or APP. The cure is to use AFCAD and turn off the back course properties for the 4R and 22L ILSs.

Share this post


Link to post
Share on other sites
Guest j-mo

Hi, Ron-Again, thanks for your reply.I was getting the left downwind. I might have been a tad faster than 180, but not much, with appropriate flaps.Examining localizer frequencies (including backcourses) isn't something I'm in the habit of doing. Maybe I should start doing this, so I appreciate the suggestion. I'll consider AFCAD, as well.As far as picking up the wrong localizer, I've been letting the PMDG 747 set the frequency,I and follow it like a puppy dog. I've only been flying it for several weeks, and am still learning some of the more subtle techniques. Regards,

Share this post


Link to post
Share on other sites

It is just an FS vs. real world oddity where the frequency is shared at both ends of a runway. There is nothing within the aircraft tuning that will cure the problem.Many of the larger airports demonstrate this problem and it could also occur with parallels as I found in a couple of instances.BTW, I use the PMDG 737NG series which is similar in the FMC/CDU operations. I check the ident in the PFD now as habit. You can see it change when you run the pattern around the back end and then approach on base to intersect. In the real world only one ILS transmitter of the pair would be turned on for the direction of landing.

Share this post


Link to post
Share on other sites

×
×
  • Create New...