First Actual IMC - Post Checkride

kjwalker01

Pre-takeoff checklist
Joined
Nov 27, 2013
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114
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Denver, CO
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Display name:
Keith
I've done a bit of actual with an instructor, even after my IFR Checkride, but yesterday was the first day I went up by myself. A lot of fun, and pretty uneventful, but I made a couple of observations:

1) And while this is obvious and well-known, I really understand just how quickly VFR pilots die in IMC. I flew from Addison, TX up to Ardmore, OK to shoot some approaches. After the last one, and a full stop/flight plan back/taxi, departed and had to make an immediate climbing 270-degree turn. About 20 seconds in, I hit the big marshmallow in the sky. I immediately felt disorientation, but knew to trust the instruments and kept everything where the should be. No problems, but without training, I know I would have stalled out/entered a spin within seconds.

2) On an RNAV approach, something just wasn't right between the GPS and autopilot. I'm fairly proficient with the 430W, but I clearly had something wrong somewhere. The IAF had a hold to establish inbound and I'm surprised the controller didn't order a breathalyzer after seeing the HP entry. The autopilot turned the wrong way and I took over doing the best I could. I think she was busy enough with other stuff to worry about it. I tried to re-engage again, but it just wasn't working right, so I just hand-flew it down. No big deal, and... and here's the observation. I quickly recognized that something wasn't right and corrected it (or in this case, took over). This was hard to do during training, as I always had an instructor next to me to talk me through this stuff.

All-in-all, I had a blast and got a huge confidence boost. Maybe next time I won't leave the car keys on the front seat in the hangar, just to make it a bit easier for someone to go get the car later. Too morbid?
 
#2 is why I do each of my currency approaches twice, once with the AP and once without. Nothing more unnerving than letting it fly and have it do something totally unexpected. I'm not 430 expert but I suspect it's notion as to what leg it was heading for was different from yours.
 
i don't think "to morbid" at all. You had a healthy respect for IMC flying. Playing a little mind game with yourself (better leave the keys in the car because I'm gonna crash and burn the airplane) to keep your focus is just fine as far as I am concerned.
 
#2 is why I do each of my currency approaches twice, once with the AP and once without. Nothing more unnerving than letting it fly and have it do something totally unexpected. I'm not 430 expert but I suspect it's notion as to what leg it was heading for was different from yours.

I think you're absolutely right. I'm about to fire up the Garmin Sim to try to duplicate that issue on that approach.
 
I think you're absolutely right. I'm about to fire up the Garmin Sim to try to duplicate that issue on that approach.
The Garmin sim will probably fly it perfectly. It may be an autopilot issue rather than a GPS issue. Especially with some older autopilots and no GPSS, you can fly to the IAF in NAV mode but you need to fly the PT in HDG mode until on an intercept for the final approach course.
 
The Garmin sim will probably fly it perfectly. It may be an autopilot issue rather than a GPS issue. Especially with some older autopilots and no GPSS, you can fly to the IAF in NAV mode but you need to fly the PT in HDG mode until on an intercept for the final approach course.

I wonder if it could be old 430 software.

I don't believe the older ones did HILPTs. The newer ones do an entry, but require suspension to go around the hold.

430s combine suspension with OBS mode, so an OBS not set to desired course could have an "interesting" effect if sequencing was suspended.
 
I wonder if it could be old 430 software.

I don't believe the older ones did HILPTs. The newer ones do an entry, but require suspension to go around the hold.

430s combine suspension with OBS mode, so an OBS not set to desired course could have an "interesting" effect if sequencing was suspended.

I'm not sure on the version. In this case, however, the GPS did show the hold, along with a parallel entry. The AP simply turned the wrong way. I didn't let it get too far, so I'm not sure what it was "thinking". I'm wondering if I had the course selector backwards on the HSI, but I didn't think there was "communication" back to the GPS and AP. It didn't make a difference on the simulator, where everything sequenced properly.
 
I wonder if it could be old 430 software.

I don't believe the older ones did HILPTs. The newer ones do an entry, but require suspension to go around the hold.

430s combine suspension with OBS mode, so an OBS not set to desired course could have an "interesting" effect if sequencing was suspended.
I see Keith pretty much answered that. That's the way I understood it originally; the hold was on the GPS but the autopilot did not fly it all by itself.

The 430/530s depicts the HILPT and, in accordance with the way they are supposed to be flown, will sequence to the FAC the next time you cross after the entry unless you tell it you want it to wait by putting it into SUSP mode.
 
I'm not sure on the version. In this case, however, the GPS did show the hold, along with a parallel entry. The AP simply turned the wrong way. I didn't let it get too far, so I'm not sure what it was "thinking". I'm wondering if I had the course selector backwards on the HSI, but I didn't think there was "communication" back to the GPS and AP. It didn't make a difference on the simulator, where everything sequenced properly.
I saw exactly that happen just a few days ago. A friend was concerned with the way the autopilot was acting so we few some approaches to test things out. Also a parallel entry. Upon crossing the IAF for the HILPT, the autopilot, like yours, flew away from the holding pattern.

We think the autopilot has some issues but that's not one of them. With GPSSteering, where the GPS tells the autopilot exactly what to do, the autopilot would follow the GPS's instruction to fly the holding pattern as depicted on the screen. Without it, at best NAV mode is simply telling the autopilot to fly to the next waypoint, without any instruction how to get there. That's why you switch to HDG mode until on an intercept course to the inbound leg of the HILPT.

The simulator's "autopilot" simulates GPSS.
 
Well, about 75% of my flight this morning was IMC. The autopilot had been giving me an attitude in the past, so I was cautious in its use. I hand flew it up, engaged it in cruise, and it started jockeying up and down after a few mins. So much so that upon disconnect, it almost threw me through my altitude limit. "No more," I said, and hand flew it the rest of the way while shooting an ILS on down. No big deal.

Technology is a great supplement. It is not to be used as a crutch. It will come around and bite you. You always have to be able to revert to hand flying. You know this, it seems. I'm just beating a dead horse.

Good to hear you learned what can happen and got a big boost in confidence. It makes you feel great.
 
Glad you had fun and made these important observations. Would have hated to see an NTSB report later that states CFIT with A/P engaged as probable cause.
Trust but verify. The A/P is here to help us control the airplane, it is not meant to replace our brains.
And Mark is right: if in doubt about the NAV mode, just use HDG to keep you straight until you get the NAV sorted out. BTDT.

Again, glad you had fun, sounds like an awesome afternoon.
I'll be having fun myself tomorrow. :)

See ya in the skies!!
 
I did my IR in a plane without an AP. Once I started flying planes with AP I felt so spoiled. I like to hand fly every other approach just to keep me in check. I also like to keep my button pushing up to speed as well.
 
I've been studying up on G1000/GFC700 approaches, and believe me, I've learned to watch the white mode annunciations.

There are a lot of details hiding in there.

430s aren't that different, but the autopilots can be. It gets REALLY bad with VNAV.

It's bad enough that I question whether the autopilot really does reduce workload, even when proficient, especially for nonprecision approaches with procedure turns. I have to prove proficiency, so I will. But dang, that's a lot of complexity for something that isn't that bad to fly by hand. So far, my experience is that a scan to hand fly isn't too hard, even with a nasty workload, but if you throw in the GFC700, that's what you're doing and there isn't much time left for scanning.

The specific approach I'm complaining about is the KSCK VOR approach (entered from ECA). I've done this several times now, both with and without the autopilot. I have a much easier time without it. It's not an easy approach, as things come at you real fast. Basically, a parallel entry with altitude loss (can be thousands of feet when arriving from the west), immediately followed by the FAF, in the zone of confusion.

http://155.178.201.160/d-tpp/1602/00407V29R.PDF
 
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So, I decided to do something crazy.... I re-read the autopilot manual and yep, right there. I have to fly the PT, or in this case the HILPT, using the heading bug. I can only assume that the heading bug was what caused the turn in the wrong direction. Sigh.... RTFM.....
 
2) On an RNAV approach, something just wasn't right between the GPS and autopilot. I'm fairly proficient with the 430W, but I clearly had something wrong somewhere. The IAF had a hold to establish inbound and I'm surprised the controller didn't order a breathalyzer after seeing the HP entry. The autopilot turned the wrong way and I took over doing the best I could. I think she was busy enough with other stuff to worry about it. I tried to re-engage again, but it just wasn't working right, so I just hand-flew it down. No big deal, and... and here's the observation. I quickly recognized that something wasn't right and corrected it (or in this case, took over). This was hard to do during training, as I always had an instructor next to me to talk me through this stuff.
Good job on catching it. Too many times flying the line I've seen pilots not paying attention when the AP is doing something wrong/uncommanded/programmed improperly. (IMO, you need just as much, if not more, attention on the instruments when coupled vs. hand-flown...)

Several weeks ago I was on a check airman observation ride with a few FAA folks; Coupled on a procedure turn inbound and the GFC700 turned towards the non-holding side, opposite of the command bars. I immediately disconnected and hand-flew it. One of the FAA observers said I had to redo it to properly show AP competency, but the lead FAA said nope, recognizing a discontinuity and manually correcting is absolutely demonstrating proficiency with that system.
 
You found the mistake before enforce it got out of hand,good job.
 
Good job on catching it. Too many times flying the line I've seen pilots not paying attention when the AP is doing something wrong/uncommanded/programmed improperly. (IMO, you need just as much, if not more, attention on the instruments when coupled vs. hand-flown...)
This.
 
So, I decided to do something crazy.... I re-read the autopilot manual and yep, right there. I have to fly the PT, or in this case the HILPT, using the heading bug. I can only assume that the heading bug was what caused the turn in the wrong direction. Sigh.... RTFM.....

Good catch.

It's best practice to point the heading bug where you expect to go, even if you aren't using it. The point is recognizing a deviation, but a side effect is that you can recover just by hitting the HDG button.
 
I did my IR in a plane without an AP
I hear ya, I'm and 3/4 of the way through my IR and am yet to fly a plane with an autopilot. I like it that way. I don't want to get spoiled too early on. I think it will make me a better pilot the more hand flying experience I get early on.
 
So, I decided to do something crazy.... I re-read the autopilot manual and yep, right there. I have to fly the PT, or in this case the HILPT, using the heading bug. I can only assume that the heading bug was what caused the turn in the wrong direction. Sigh.... RTFM.....
I'm not sure your assumption is correct. If you were still in NAV mode (which it sounds like since you were expecting the autopilot to fly the reversal itself), the position of the heading bug would not have made a difference. You also need to switch to HDG mode. What I think is more likely is, assuming you were still in NAV mode, the GPS sequenced to the next waypoint, the FAF. But the autopilot had no idea how to get there.
 
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