Garmin 430 "Steep Turn Ahead"

SixPapaCharlie

SixPapaCharlie

May the force be with you
Joined
Aug 8, 2013
Messages
16,415
Display Name
Display name:
Sixer
Today whilst flying an RNAV in to Gainesville Municipal, I loaded the departure, flew it, then loaded the approach and then was told to go direct Ilopy.

Around where the red X is, I went FPL, Ilopy, Direct Enter Enter and all was right with the world.
The Garmin showed the teardrop magenta procedure turn but just about a mile before the IAF,
the 430 starts flashing "Steep Turn Ahead"

Just before getting to the fix, the plane veers about 90 degrees to the east. I killed it and hand flew it.

I have never seen "steep turn ahead". Also if it clearly showed I was going to the IAF, procedure turn to rejoin final, what might cause it to decide I needed to be off to the east?

Very confusing. Baffled my instructor and an other instructor we spoke to after landing.
Approach was loaded but not activated. For grins after I it tried to turn, I activated the approach just to see what it would do and then it wanted to go to WALON IAF which kind of makes sense.

But why the steep turn alert and turning off course.
ilopy.jpg
 
Last edited:
Follow up. What if by mistake, I accidentally went direct Lutny (FAF) instead of ILOPY (IAF)
Would a buttonology mistake cause the behavior I experienced?

At location X if I wen direct LUTNY what would the Garmin tell the auto pilot to do?
When I was typing the OP, I accidentally typed LUTNY twice and realized my mistake and went back and corrected it in the post. Obviously my brain transposes those two. Perhaps I made the same clerical error in the Garmin.

Would that do it?
 
Who knows wtf u did. Uh I mean who knows what your gps did. But I’m leaning towards you loaded the approach with TEYUS as the transition and then went direct teyus. But really who knows.
 
In my brief time using the 430, I wouldn't trust the approach to activate with a HILPT, so I just put in a hold at the IF and then activated the approach half way through the turn.

It may be a ghetto way to get it done, but it always worked. YMMV.

I'm not a Garmin guy, so keep your disgust to a minimum, k?
 
SixPapaCharlie said:
Today whilst flying an RNAV in to Gainesville Municipal, I loaded the departure, flew it, then loaded the approach and then was told to go direct Ilopy.

Around where the red X is, I went FPL, Ilopy, Direct Enter Enter and all was right with the world.
he Garmin showed the teardrop magenta procedure turn but just about a mile before the IAF,
the 430 starts flashing "Steep Turn Ahead"

Just before getting to the fix, the plane veers about 90 degrees to the east. I killed it and hand flew it.

I have never seen "steep turn ahead". Also if it clearly showed I was going to the IAF, procedure turn to rejoin final, what might cause it to decide I needed to be off to the east?

Very confusing. Baffled my instructor and an other instructor we spoke to after landing.
Approach was loaded but not activated. For grins after I it tried to turn, I activated the approach just to see what it would do and then it wanted to go to WALON IAF which kind of makes sense.

But why the steep turn alert and turning off course.
View attachment 97299
Click to expand...

You were flying an RNAV. You loaded a Departure. What Departure? Departure to where? What was in the FPL when you did that? Did you go through a ‘Select Approach’ entry at anytime during all this?
 
Last edited:
@SixPapaCharlie, N55WB will be back very soon with the new avionics and GFC500 autopilot.

Your query has me curious about why your 430 and STEC55x did that. I have flown that same route with the older avionics (CNX80 and Chelton autopilot) and it behaves as you were expecting.

And I’d like to see what happens if I fly that same profile with the new equipment. You are most invited to come along when I do that.
 
The one piece of this that I can comment on is that when you activate an approach on the Garmin navigators that I've used, it will take you direct from your present position to whichever IAF you previously selected. (I don't know what it will do if you selected vectors.)
 
luvflyin said:
You were flying an RNAV. You loaded a Departure. What Departure? Departure to where? What was in the FPL when you did that? Did you go through a ‘Select Approach’ entry at anytime during all this?
Click to expand...

TEX1 departure out of Denton KDTO
BLECO transition.

Took off.

Direct BLECO.

Loaded RNAV 18 GLE. did not activate yet.
Direct ILOPY then the steep turn warning after a few minutes inbound.

I have been unable to recreate this in my Garmin emulator or X-Plane using the same avionics.
 
AggieMike88 said:
@SixPapaCharlie, N55WB will be back very soon with the new avionics and GFC500 autopilot.

Your query has me curious about why your 430 and STEC55x did that. I have flown that same route with the older avionics (CNX80 and Chelton autopilot) and it behaves as you were expecting.

And I’d like to see what happens if I fly that same profile with the new equipment. You are most invited to come along when I do that.
Click to expand...

If you do that, let me know what happens. I'm happy to tag along if it's after my check ride. Right now I am religiously only flying the cirrus and with only two people. I have some very specific dominoes that need to fall in order right after the check ride.
 
SixPapaCharlie said:
TEX1 departure out of Denton KDTO
BLECO transition.

Took off.

Direct BLECO.

Loaded RNAV 18 GLE. did not activate yet.
Direct ILOPY then the steep turn warning after a few minutes inbound.

I have been unable to recreate this in my Garmin emulator or X-Plane using the same avionics.
Click to expand...
You loaded the approach and selected which IAF ?
 
you need a different approach..........to that approach. fly it again without the DP and see what happens (really that's just an excuse to go flying again....)
 
MacFlier said:
You loaded the approach and selected which IAF ?
Click to expand...

@SixPapaCharlie . This question^^^. Before loading an Approach, you must select an Approach. When doing so, you select an IAF or Vectors to final. Do you remember what you did? When you select the RNAV(GPS)RWY18, which is the first IAF on the list. I’m thinking WALON somehow got mixed up in all of this.
 
Is there any chance the 430 asked if you wanted to fly the course reversal at ILOPY and you chose NO by mistake? I don't think it usually asks that question when the turn would be as steep as this, but I haven't been in that scenario recently enough to remember for sure.
 
SixPapaCharlie said:
Loaded and selected WALON initially.
Then entered direct ILOPY
Click to expand...

Thought so. Exactly how that skewed things, I dunno. Voices in my head are saying the Autopilot may be where to look to find the smoking gun. You said you killed the AP and hand flew it. Was there a pretty magenta racetrack on the screen while you were doing that?
 
Last edited:
:needpics:
unless you have evidence of what it was turning toward, it’s all guesswork that mostly points to fat-fingered programming.:dunno:
 
MauleSkinner said:
:needpics:
unless you have evidence of what it was turning toward, it’s all guesswork that mostly points to fat-fingered programming.:dunno:
Click to expand...

It’s a 430. Not so much a ‘fat fingers’ thang. More like a I got blisters on my fingers thang from click click...click ENTER, repeat gawd only knows how many times to get a task done.

 
luvflyin said:
click click...click ENTER
Click to expand...

Turn turn turn turn turn ENT turn turn turn turn turn turn turn turn turn ENT turn turn turn....

Carpal tunnel syndrome inducing.

But at least those knobs give me something to hang on to in turbulence.

Side note sort of related to the sharp turn - our AP likes to attack the hold and fly it exactly as the 430w draws it... which results in a > standard rate turn and high bank angle. Which gets fun in IMC. And my fun I mean not fun and disorienting. Still trying to figure out that setting between Garmin and Trutrack...
 
luvflyin said:
Thought so. Exactly how that skewed things, I dunno. Voices in my head are saying the Autopilot may be where to look to find the smoking gun. You said you killed the AP and hand flew it. Was there a pretty magenta racetrack on the screen while you were doing that?
Click to expand...
It is a mistery why it would have you turn left instead of fly the course reversal. Maybe, like someone mentioned, you declined the course reversal? Or instead of doing direct to ILOPY from the approach segment in the FPL page you used ILOPY as a regular waypoint outside the approach?
 
MacFlier said:
It is a mistery why it would have you turn left instead of fly the course reversal. Maybe, like someone mentioned, you declined the course reversal? Or instead of doing direct to ILOPY from the approach segment in the FPL page you used ILOPY as a regular waypoint outside the approach?
Click to expand...

You may be on to something here. @SixPapaCharlie , ya still here?
 
Last edited:
Why did you select ILOPY after setting up the approach? That's what started the chaos.

The flight plan in the 430 probably read like this:

BLECO - or something like that
TEYUS
WALON
ILOPY
LUTNY
GODNE
KGLE - or maybe runway 18
-- then the missed info here --

You didn't activate the approach. Then you skipped into ILOPY. At the angle you drew it would be a steep left turn to get onto the course from ILOPY to LUTNY. So, the Steep Turn Ahead warning was correct. Does that help?

I'm not sure why the 90* turn to the east. What did the 430 say it was doing at that point? What was it showing as the course? Where was it in the flight plan?

Is it a 430 or 430W?
 
I'm betting when you loaded the approach you selected WALON as the IAF. After the box flew the last direct leg with no further inputs, its next step would be to sequence you to the approach you had loaded, so it was telling you it was going to turn hard right direct WALON after ILOPY, which it looks like it tried to do before you clicked off the AP.

I would have reloaded the approach starting at ILOPY if I'd gotten that clearance (and was expecting the full approach from ILOPY). It also might have worked to activate the WALON -> ILOPY leg (D-> D-> enter) and then activate the approach but I'm not 100% on that.

What happened after you started hand flying and activated the approach? Did it automatically sequence to the course reversal at ILOPY or did you have to manually activate the leg?
 
luvflyin said:
Thought so. Exactly how that skewed things, I dunno. Voices in my head are saying the Autopilot may be where to look to find the smoking gun. You said you killed the AP and hand flew it. Was there a pretty magenta racetrack on the screen while you were doing that?
Click to expand...
yes
 
I am going to go re-fly this exact thing tomorrow and I will bring a gopro to record the 430
 
wayne said:
Why did you select ILOPY after setting up the approach? That's what started the chaos.

Is it a 430 or 430W?
Click to expand...

ATC (CFI) said "25MV proceed direct ILOPY"

It is a 430W
 
If you load your destination, then load your approach but not activate it, doesn’t that leave the next waypoint in your flight plan as the destination airport?
 
Hold on……you’re NOT supposed to do steep turns in IMC?
 
@SixPapaCharlie, You selected WALON as the IAF, at that point, even though it is charted as an IAF, ILOPY is just the next fix on the approach. When you selected Direct ILOPY, the GPS is going to go direct to that fix, but then go direct LUTNY because that is the next fix on the approach. Because its such a sharp turn, the GPS really doesn’t know how to do it. What is causing the confusion is that the holding turn in lieu of a procedure turn is identical to the holding pattern for the missed approach. So as you had it set up, the “picture” looked like you where set up to do a procedure turn, but the flight plan would have showed to true story. In this particular case, what you would have had to do is re-enter the approach and then selected ILOPY as the IAF.

Make sense?
 
On a positive note, you didn’t let the automation do something you didn’t want it to do, and safely flew the approach. You are closer to ready for your Checkride than you think.
 
SixPapaCharlie said:
Loaded and selected WALON initially.
Then entered direct ILOPY
Click to expand...

Dave Theisen said:
You selected WALON as the IAF, at that point, even though it is charted as an IAF, ILOPY is just the next fix on the approach. When you selected Direct ILOPY, the GPS is going to go direct to that fix, but then go direct LUTNY because that is the next fix on the approach
Click to expand...

Dave nailed it. You selected WALON as the IAF. There is NoPT from WALON. Then you hit Direct ILOPY. The next fix after Direct ILOPY was LUTNY. Looks like a 170° turn from your drawing, I guess I would call that "sharp" rather than "steep" but close enough.

Additionally, whether the approach was activated or not doesn't matter. In Garmin-speak, activating an approach just means going Direct-to the first fix.
 
You must log in or register to reply here.
Back
Top