Garmin 430 how to deviate for weather, then return to FP

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jeffs chips

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Hello, private pilot headed into IFR ticket and can't find a video or tutorial on how to deviate for weather (or anything) when on a garmin 430 flight plan, then, after passing obstacle, return to flight plan. Is it as simple as switching to heading mode, changing heading by say a certain amount of degrees, then once past the obstacle, going back to gpss mode and thereby getting back on course via autopilot?

Thanks in advance.
 
Yes.

Switch to heading mode, take care of deviation.

Then >D> ENTER ENTER to proceed from present position to the selected waypoint.


Don't forget there is a downloadable sim that is perfect for playing with scenarios and questions such as this.
 
I like your method better if the deviation is small. Reason being is if your clearance is on a victor airway- leaving flight plan in will help your establish faster back on the airway.
If you D->enter enter to next waypoint you aren’t necessarily going to be on the airway anymore.
If you have a larger deviation your clearance might change a bit so the D- enter enter method is better.
 
benyflyguy said:
I like your method better if the deviation is small. Reason being is if your clearance is on a victor airway- leaving flight plan in will help your establish faster back on the airway.
If you D->enter enter to next waypoint you aren’t necessarily going to be on the airway anymore.
If you have a larger deviation your clearance might change a bit so the D- enter enter method is better.
Click to expand...

Right.

There’s an accident chain video out there about this.
A turboprop commander or something like that leaving Arizona at night with family onboard. Deviated for whatever reason and then D-> ent ent.

Then later controlled flight into terrain. Not enough terrain clearance for the new route.
 
Both of you guys I agree with if an airway was involved and terrain clearance was tight. So take care of the deviation, but be mindful how far off of the airway you are getting and how much clearance you have over the terrain. Then when deviation is sorted, use the NAV function of your autopilot and the OBS of the CDI to reintercept the radial. Once established back on airway, switch to GPSS and continue.

But keep in mind, this is PoA and the interwebz, so picking of all sorts of nits is fair game. That said, the OP didn't specify airway. So.... nyah!:p:p
 
All very useful and enlightening. Thanks for the link to the sad story. So the moral of the story is be aware of terrain clearance and obstructions at all times.
 
jeffs chips said:
All very useful and enlightening. Thanks for the link to the sad story. So the moral of the story is be aware of terrain clearance and obstructions at all times.
Click to expand...

Yup. Moral #1. The Big Moral. The HMIC (head moral in charge.) There are many other sad stories about not knowing where the rocks are and where you are.
 
jeffs chips said:
Hello, private pilot headed into IFR ticket and can't find a video or tutorial on how to deviate for weather (or anything) when on a garmin 430 flight plan, then, after passing obstacle, return to flight plan. Is it as simple as switching to heading mode, changing heading by say a certain amount of degrees, then once past the obstacle, going back to gpss mode and thereby getting back on course via autopilot?

Thanks in advance.
Click to expand...

That simple except there are times when you may not want to go back to gpss mode once past the obstacle. Sometimes ATC will clear you direct to a Waypoint up the up the road you already have loaded in your Flight Plan, then it’s easy. Sometimes they may want to vector you back to the route before then. Like “fly heading ###, join Victor##, resume own navigation. When you change back to gpss from heading mode will depend on the situation.

EDIT: @jeffs chips , it just dawned on me I was thinking of GPS in general, not GPSS. Read below
 
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luvflyin said:
... “fly heading ###, join Victor##, resume own navigation. When you change back to gpss from heading mode will depend on the situation.
Click to expand...
Isn’t it two pushes of the DIRECT button to activate the flight plan course to the fix rather than just going direct to the fix?
 
MauleSkinner said:
Isn’t it two pushes of the DIRECT button to activate the flight plan course to the fix rather than just going direct to the fix?
Click to expand...

I dunno. Just edited my post above. I’ve never used gpsS much less even any autopilot.
 
I'd hit the FPL button, pick the segment I want to rejoin, and activate.

[Note: I'm VFR only, but I do have to deviate to avoid them clouds I'm not allowed to fly through]
 
As I heard a testy controller state: "Resume own nav means go back to the assigned route, not direct to destination."

If the fixes in your plan are close together, going Direct to the next one probably is as good as any. If they are sufficiently far apart, you'll probably have to give the thing a help. On my 480/Stec combo, I'd make sure the proper segment is still active and then set a heading that will put me towards where I want to intercept and punch both the HDG and NAV buttons which will follow the HDG until the intercept occurs.
 
MauleSkinner said:
Isn’t it two pushes of the DIRECT button to activate the flight plan course to the fix rather than just going direct to the fix?
Click to expand...
Yes. DIRECT gives to direct to the next waypoint; DIRECT DIRECT give you the flight plan leg interception.
upload_2019-6-2_11-23-58.png

flyingron said:
As I heard a testy controller state: "Resume own nav means go back to the assigned route, not direct to destination."
Click to expand...
Solution is easy. In the readback tell the controller what you are going to do. Let Mr Testy correct you if he wants, so long as yo are ultimately on the same page.
 
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midlifeflyer said:
Yes. DIRECT gives to direct to the next waypoint; DICET DIRECT give you the flight plan leg interception.
View attachment 74563


Solution is easy. In the readback tell the controller what you are going to do. Let Mr Testy correct you if he wants, so long as yo are ultimately on the same page.
Click to expand...

What does it pick for the interception angle. Some hard number like maybe 30 degrees? Depends on how far off and out you are?
 
luvflyin said:
What does it pick for the interception angle. Some hard number like maybe 30 degrees? Depends on how far off and out you are?
Click to expand...

Unless you have GPSS installed, your autopilot will not automatically re-join the airway. WIthout GPSS, you would dial in a reasonable intercept heading from your current position, fly until on the airway, then turn to the appropriate airway heading before re-engaging the autopilot. My STEC-20 will not capture an assigned routing unless it is within +/- 10 degrees of the desired heading. If off by more than that, it may eventually capture, but not after a lot of seasick scalloping. I don't have GPSS yet, so I don't know how well it copes with a large cross-track error and a large intercept angle.

When flying IFR, it's always good to have a sectional chart open (That's my default view on my EFB) so you can see the minimum safe altitude for the quadrant you are flying in. That way, if you are solid IMC making deviations, you at least know if you are safely above obstacles. ATC will normally help as well when you go off course for weather, but they are not PIC.

If you want to go direct to the next waypoint instead of re-joining the airway or previous routing, it's always a good idea to confirm with ATC. Often, ATC will beat you to that request and just offer a clearance direct if in radar contact and you are above MVA.
 
chemgeek said:
Unless you have GPSS installed, your autopilot will not automatically re-join the airway. WIthout GPSS, you would dial in a reasonable intercept heading from your current position, fly until on the airway, then turn to the appropriate airway heading before re-engaging the autopilot. My STEC-20 will not capture an assigned routing unless it is within +/- 10 degrees of the desired heading. If off by more than that, it may eventually capture, but not after a lot of seasick scalloping. I don't have GPSS yet, so I don't know how well it copes with a large cross-track error and a large intercept angle.

When flying IFR, it's always good to have a sectional chart open (That's my default view on my EFB) so you can see the minimum safe altitude for the quadrant you are flying in. That way, if you are solid IMC making deviations, you at least know if you are safely above obstacles. ATC will normally help as well when you go off course for weather, but they are not PIC.

If you want to go direct to the next waypoint instead of re-joining the airway or previous routing, it's always a good idea to confirm with ATC. Often, ATC will beat you to that request and just offer a clearance direct if in radar contact and you are above MVA.
Click to expand...

Be careful of what you might be calling minimum safe altitudes on Sectionals. I think your thinking of MEF’s. Those altitudes in each Quadrangle. It’s Maximum Elevation Figure. The height above the highest terrain in the quadrangle plus 200 feet for any uncharted obstructions plus 100 feet for error then round up. If the highest thing is man made obstruction then it’s that plus 100 feet for error then round up. That altitude could put you within 100 feet of something but it’s usually a little higher. If your using them as a minimum safe altitude for IFR you better be adding around a 1000 feet to them.
 
On the GTN series one may choose to continuously display MSA on the screen.
 
luvflyin said:
What does it pick for the interception angle. Some hard number like maybe 30 degrees? Depends on how far off and out you are?
Click to expand...
If you are going to intercept the current leg, you pick your intercept angle, just as you would without GPS. With an autopilot, you are already in heading mode for the deviation. Rotate to a reasonable intercept heading and, depending on the autopilot, arm nav mode or wait to switch to it when close enough for it to take over. A GPSS system might do most if it for you.
 
If you are wanting to go back to the original course(why) you could also use the OBS function and have it Place the magenta line back...I.e. an airway
 
luvflyin said:
Be careful of what you might be calling minimum safe altitudes on Sectionals. I think your thinking of MEF’s. Those altitudes in each Quadrangle. It’s Maximum Elevation Figure. The height above the highest terrain in the quadrangle plus 200 feet for any uncharted obstructions plus 100 feet for error then round up. If the highest thing is man made obstruction then it’s that plus 100 feet for error then round up. That altitude could put you within 100 feet of something but it’s usually a little higher. If your using them as a minimum safe altitude for IFR you better be adding around a 1000 feet to them.
Click to expand...

Yes, what you really want is the off-route altitude on the IFR Enroute charts.

oroca.jpg
 
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