Help with Manuel Sequence |
Post Reply |
Author | |
Craig767
Groupie Joined: 17 Dec 2014 Location: Gainesville, FL Status: Offline Points: 98 |
Post Options
Thanks(0)
Posted: 26 Jan 2016 at 7:37pm |
Don't know if this problem is me or the 540. The ILS 36 app into KOCF Ocala, FL is giving me problems with the missed app. The app plate reads as follows: Missed Approach: climb to 3000ft via OCF VORTAC R-355 to LEJKO INT/OCF VORTAC 10 DME and hold. Continue climb in hold to 3000ft.The missed app in the 540 ends up being:
Don't know why there is a climb to leg inserted in the miss. Assume it is a Jepp or Avidyne issue. Anyway on the app everything is looking good after FAF inbound. Miss looks to be armed. On arrival at MAP get the "Manuel Sequence Req" caution. Ok I know what to do with this, after climb established and aircraft cleaned up I push the "Manuel Sequence" LSK. The result is not what I expected, the missed app routing disappeared and was left with the white dots showing the miss. Tried entering direct to the MAP fix but the 540 would not allow that. This was on a practice app in VMC by the way. So did I do something wrong or did the 540 have a malfunction when I pushed the LSK. Thanks |
|
AviJake
Admin Group Joined: 26 Mar 2009 Location: Lincoln MA Status: Offline Points: 2815 |
Post Options
Thanks(0)
|
Most missed approaches start with a leg to climb on runway heading to 400 AGL. Although they are not typically represented on a paper chart, those legs are specified in the navigation database from Jeppesen. In the KOCF case, as you noted, that first missed approach leg is followed by a 355° course leg to the hold fix and then the hold.
The missed approach should have been inactive until you passed the FAF. At that point, with Auto-Enable Missed selected on the setup page, the system would have enabled the missed approach. Once you sequenced the MAP and went missed, the climb leg would have become active, thus causing the system to present the "Manual Sequence Req'd" alert and the associated "Sequence Leg" LSK on the plan page. When you pressed the LSK, that should have made the 355° course leg active and then guidance would be provided to steer along that leg. I'm not sure why you would have seen white dots presented for the missed. We couldn't reproduce such behavior.
You mentioned that you couldn't go direct-to the MAP, but there is no restriction on doing that, so I'm not sure what steps you might have taken. I wonder if you instead meant to say "MAH", but there's no restriction on that either. Doing a direct-to the hold fix wouldn't activate the hold, but the leg prior to the hold.
Did you see the white dots on the IFD display or a secondary display, such as an MFD?
Here are some screen shots of our attempt to reproduce this. The first shot should look familiar as it is just after sequencing the MAP and before the Sequence Leg LSK has been pressed. The second shot is what you should have seen after having pressed the LSK. Notice that the leg to the hold fix has become active. |
|
Steve Jacobson
sjacobson@avidyne.com |
|
Craig767
Groupie Joined: 17 Dec 2014 Location: Gainesville, FL Status: Offline Points: 98 |
Post Options
Thanks(0)
|
Thanks for the reply Steve
I am assuming that the apps with the RWH and 400ft are the ILS or LPV or could I get the same with a LNAV app with MDA? So anytime I see the first segment on the miss as a climb to I can expect to get the Manuel Sequence Caution in my aircraft. Everything on the ILS 36 was normal until I pushed the LSK manual sequence button. The white dots I saw after I pushed were on the 540. Your right I had a typo, was trying to say that I tried going direct to the miss app fix. Was in FPL and tried highlighting the fix to use the direct key. For some reason that did not work. Did not try the direct key and entering the fix that way. Was wondering do we get any "Manual Sequencing Req" on the 540 iPad sim. Don't remember seeing any of those. |
|
Catani
Senior Member Joined: 21 Jan 2016 Status: Offline Points: 362 |
Post Options
Thanks(0)
|
This is getting a bit far afield from how to operate an IFD540/440, and probably belongs on an IFR webstie somewhere. Nevertheless, the IFD540/440 is the device on which appears the instruction to climb straight ahead and to ignore the missed approach procedure temporarily, so here goes: That is something I had not noticed, and I wonder why it's so. For instrument takeoffs, TERPS requires, for standard obstacle clearance, a climb to 400 AGL, and assumes you're only at 35 feet at the far end of the runway for purposes of identifying those critical obstacles. But MAPs are typically started at MDA or DH altitudes where you are at or before the approach end of the runway, or at worst sometime later on very short final when you realize the field has just disappeared. So flying an MAP leaves you much higher than anybody would be on a takeoff in the same airplane who started the takeoff roll at the same time you initiated the missed. Additionally, if there are any obstacles to take into account on a MAP, they are done in the process of designing the MAP itself. In other words, if the MAP says to "turn left, climb to 2000, proceed to the holding fix" then you should be able to do just that, starting at 200 feet DH. It's clear why the IFD540/440 requires the climb to 400 AGL at KOCF - Jepp says so in the database that's loaded into the IFD. It's not clear to me why Jepp says so, however. Perhaps it is because of that rule that says you have to go missed if you lose sight of the runway environment after the MAP - which could put you close to runway elevation, theoretically, just as you are on takeoff roll. Still, I've not seen any publication that takes note of that possibility and recommends a straight ahead climb to 400 AGL on a missed regardless of what the MAP procedure says. What if there were an obstacle off the end of the runway that would make climbing straight ahead more dangerous than executing an immediate left turn as some MAP procedure might require? Also, the fact that the IFD540/440 is programmed to portray the database's initial climb means the pilot has to remember to take the extra step of sequencing the MAP, which in my mind should not be necessary. I don't see the added safety in that. I'm puzzled.
|
|
AviJake
Admin Group Joined: 26 Mar 2009 Location: Lincoln MA Status: Offline Points: 2815 |
Post Options
Thanks(0)
|
The climb to 400 AGL legs occur on all kinds of approaches, not just ILS and LPV. Those legs are included by Jeppesen as a result of database coding rules specified in ARINC-424. The "Manual Sequence Req'd" alert is issued because your system does not have a baro altitude input wired into the IFD. Since the IFD doesn't know your baro altitude, it does not know when to sequence those legs. So, we count on the pilot to notify the FMS when the specified altitude has been reached. You don't see that alert in the simulator because the simulator assumes that it has a baro altitude input. We still don't know why you saw the white dots on the IFD. About the only thing we can imagine that is you re-activated a leg on the approach that was before the FAF (or to the FAF). When you are on a leg in that part of the approach, the missed is disabled again until you pass the FAF. I would encourage you to try this approach again now that you are more familiar with what to expect. If it still happens, then we can get logs from you and figure out what's happening. |
|
Steve Jacobson
sjacobson@avidyne.com |
|
chflyer
Senior Member Joined: 24 Jan 2013 Location: LSZK Status: Offline Points: 1022 |
Post Options
Thanks(0)
|
My installation has the IFD540 receiving RS232/2 altitude data from an SAE 5-35 on P1001 pin 59. Does this qualify as "baro altitude input" for the purpose of automatic sequencing in your explanation above?
The 540/440 IM par 6.8.1.1 gives this as an uncorrected pressure altitude source rather than a baro altitude source per 6.8.1.2. Edited by chflyer - 29 Jan 2016 at 4:25pm |
|
Vince
|
|
roltman
Senior Member Joined: 04 Aug 2011 Status: Offline Points: 173 |
Post Options
Thanks(0)
|
The SAE 5-35 will only give you an uncorrected pressure altitude and will not automatically sequence you. In the Sandia product line you would need the SAE 7-35 to do the automatic sequencing. |
|
chflyer
Senior Member Joined: 24 Jan 2013 Location: LSZK Status: Offline Points: 1022 |
Post Options
Thanks(0)
|
I thought that with 10.1.1.0 the gps altitude was also accepted, or am I confusing with some other altitude requirement that is now met with gps altitude?
Edited by chflyer - 30 Jan 2016 at 2:31am |
|
Vince
|
|
bneub111
Newbie Joined: 16 Feb 2015 Status: Offline Points: 33 |
Post Options
Thanks(0)
|
This question has probably been asked before, but why can't the altimeter setting just be entered into a 540? Obviously that would require some software but I'm sure it is capable of doing the math to adjust pressure altitude from the encoder.
|
|
roltman
Senior Member Joined: 04 Aug 2011 Status: Offline Points: 173 |
Post Options
Thanks(0)
|
10.1.1.0 I believe was using GPS alt for VSR calculations only. AviJake can comment; however GPS altitude is not valid substitution for actual precision approach altitudes.
|
|
roltman
Senior Member Joined: 04 Aug 2011 Status: Offline Points: 173 |
Post Options
Thanks(0)
|
Jake this post reminds me. Change the baro input to automatically assume the "." in it. To me it makes sense to press 3 0 0 0 to get 30.00 instead of 3 0 . 0 0. Maybe it was changed in 10.1.1.0 as I don't recall punching in a baro setting after that update. |
|
AviJake
Admin Group Joined: 26 Mar 2009 Location: Lincoln MA Status: Offline Points: 2815 |
Post Options
Thanks(0)
|
Agreed.
|
|
Steve Jacobson
sjacobson@avidyne.com |
|
AviJake
Admin Group Joined: 26 Mar 2009 Location: Lincoln MA Status: Offline Points: 2815 |
Post Options
Thanks(0)
|
No, we didn't remove the requirement to enter a decimal point if that's what your asking but it's a good idea that I'll enter in the database now.
|
|
Steve Jacobson
sjacobson@avidyne.com |
|
AzAv8r
Senior Member Joined: 06 Dec 2011 Location: Arizona Status: Offline Points: 154 |
Post Options
Thanks(0)
|
Where/when is there a baro input? I understand the use, I just don't ever recall seeing a means/screen to enter it.
You could make it like the frequency entry, and also infer the first digit if it is not a 2 or 3. "014" becomes 30.14, "965" becomes 29.65. |
|
AviJake
Admin Group Joined: 26 Mar 2009 Location: Lincoln MA Status: Offline Points: 2815 |
Post Options
Thanks(0)
|
Air Data calculator utility.
|
|
Steve Jacobson
sjacobson@avidyne.com |
|
chflyer
Senior Member Joined: 24 Jan 2013 Location: LSZK Status: Offline Points: 1022 |
Post Options
Thanks(0)
|
If an altitude encoder cannot substitute for adc baro alt input, what IFD functionality is added with an encoder rs232 feed to the IFD?
Vince |
|
Vince
|
|
oskrypuch
Senior Member Joined: 09 Nov 2012 Location: CYFD Status: Offline Points: 3058 |
Post Options
Thanks(0)
|
On departures, climb to altitude legs will require a manual sequencing.
But VSR will work, and TOD will also be calculated. * Orest |
|
AviJake
Admin Group Joined: 26 Mar 2009 Location: Lincoln MA Status: Offline Points: 2815 |
Post Options
Thanks(0)
|
Right.
|
|
Steve Jacobson
sjacobson@avidyne.com |
|
DavidBunin
Senior Member Joined: 20 May 2015 Location: Rockwall, TX Status: Offline Points: 742 |
Post Options
Thanks(0)
|
Isn't the Pressure Altitude value from the encoder also used as some kind of sanity check for the GPS position solution? Especially when WAAS is unavailable.
David Bunin |
|
Post Reply | |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |