Ifr approach

[Tracker]

Flying an M20R with G1000 and with an stec 55x autopilot.

Before flying this wonderful airplane my procedure for ifr approaches was to fly to minimums and if I acquire adequate runways indications apply landing flaps and land.

With Stec autopilot I disengage the autopilot at 1000 feet fly the rest of the approach by hand and use the landing flaps as above.  If I miss I start the missed procedure, engage the autopilot on hdg and vs mode at 1000 feet and engage the nav mode after I have sequenced the gps to missed procedure.

I recently flew with an instructor in a Diamond twin star simulator to improve my IFR skills. He suggested that I let the autopilot go down to minimums and if landing don’t drop the remaining flaps and trim should be correct.

The pluses of my technique I think is I have a feel for the plane for at least for a minute before I land and I use full flaps.  The instructor’s technique would allow me to concentrate on runway acquisition and not change the aircraft configuration close to the ground.  Down side a lot to do in a missed with no go around button and only takeoff flaps.
 

Interested in how others fly the last segment of the approach (particularly with G1000 and the Stec 55x)

 

 

 

 

[PT20J]

With modern glass cockpits and capable autopilots, I let the autopilot fly to minimums. This is the way professional pilots do it. The reason is that it relieves you of the mechanics of flying and gives you the ability to monitor what's going on increases situational awareness. I keep a hand on the yoke in case something goes awry with the automation, but I can monitor the autopilot and control airspeed while devoting more time to looking ahead for the runway environment. The autopilot will fly more precisely than I can - that's why autopilots are required for operators authorized for minimums below 200'.

It's still a good idea to fly some approaches manually to avoid becoming automation dependent. But if the weather is really down to minimums, I use the autopilot. I fly my approaches at 90 KIAS and TO flaps. From 200', it's really no problem to stay on the GS/GP and add full flaps and slow to Vref. 

Skip

[GeeBee]

I have the same set up as you. 

Keep in mind the minimum engagement altitude for the S-Tec 55x is 240' so if you are going to 200' HAT you need to disconnect early.

In reality IMHO there is nothing wrong with either approach. I would say, "It depends" Why?

If you are going to the bottom of the barrel, 200' HAT with full flaps disconnecting at 1000' and hand flying is better than disconnecting at 240'. Further if you are going full flaps the S-Tec does not trim quickly enough to handle the addition of full flaps and stay on the GS. It can in fact be a little bit of a wild ride.  If you are going to land full flaps, either disconnect and hand fly before full flaps or go full flaps down just before GS interception and leave the A/P engaged to 240'. It takes a lot of power but that is the only way I do full flaps because of the slow trim.

If you do it the instructors way, nothing wrong with that, in fact if you have or encountered icing conditions you should land with T/O flaps even with a TKS airplane (It's a limitation on TKS airplanes). However you still have to plan on a disconnect by 240' HAT. Airplane will be in trim until the flare and the down side is your approach speed is a little higher which is not good for a wet runway, but manageable.

In both cases the climb performance in a missed approach is acceptable, the autopilot in V/S will make acceptable trim changes with the flaps, just make sure you arm ALT when you press V/S and verify ALT (White) on the PFD.

 

[Will.iam]

Don’t know about the STEC autopilot but my KFC-150 has a limitation not to exceed 10 degrees of flaps. This also makes it much easier on the go around and as another pilot pointed out there is no instrument approach procedure that goes to a runway shorter than you would need more than 10 degrees of flaps to be able to land at.  

[McMooney]

I configure the plane, takeoff flaps, prop,  radios, etc. between the IF and FAF, at FAF/intercept I drop gear and ride it down to the runway.  No configuration changes after the FAF,  land or redo.  Sometimes i use the Brittain but it's only single axis.

[Tracker]

Thanks for the responses.  GeeBee,  aware of the limitation for flaps limited to takeoff configuration after encountering ice. Was not aware of the stec g/s limitation to 240 feet.  Did not see it in the stec manual.  Could you tell me where to find it? 

[Z W]

I also use only half flaps for approaches.  Much easier on the go-around. If you have full flaps out, trimmed for 80-90 KIAS or so, and firewall the throttle, the plane will very strongly pitch up, requiring a lot of force to keep the proper climb attitude.  It's distracting to the pilot and concerning to passengers.  

If I break out in time, I'll add full flaps before landing, but landing with only the half flaps is a non-event on any runway I'm shooting an approach to.

I also find the plane feels much more stable on the approach at 80-90KIAS with half flaps than full.

[GeeBee]

2 hours ago, Tracker said:

Thanks for the responses.  GeeBee,  aware of the limitation for flaps limited to takeoff configuration after encountering ice. Was not aware of the stec g/s limitation to 240 feet.  Did not see it in the stec manual.  Could you tell me where to find it? 

If memory serves me correctly it is in the POH supplement. It is 400' general engagement and 240' in the approach mode.

[PT20J]

1 hour ago, GeeBee said:

If memory serves me correctly it is in the POH supplement. It is 400' general engagement and 240' in the approach mode.

THIS ^^^^^ The limitations are specific to each airframe and will be in the AFMS. The Cirrus I flew with a 55X had the limitation of 100’ below MDA (non-precision approach), or DH (precision approach).

[Deb]

4 hours ago, Tracker said:

Was not aware of the stec g/s limitation to 240 feet.  Did not see it in the stec manual.  Could you tell me where to find it? 

As Greg posted, it’s in the POH supplement:

[MatthiasArnold]

Having the exact same configuration, here is the way I'm doing it (which may be met with criticism ):

I hand-fly 95%+ of all my IFR approaches to minimum..

There are several reasons why I do it like this:

• I've learned it that way
• I want to stay proficient in hand-flying IFR
• I'm not very satisfied with the performance of the rate-based S-TEC 55X (GFC700 would be a different story)
• BTW: when utilizing the FPM of SVT, hand flying IFR approaches is really easy (I installed the option app. a year ago).

Background

• Since I'm not based at an airfield with IFR approaches app. 75% of my IFR approaches are training approaches at airports like (Cologne, Liege, Dortmund, Frankfurt-Hahn)
• In order to stay proficient, I try to fly at least 2 IFR training approaches (1 x 3D with 200ft DH + 1 x 2D) every 2-3 weeks.
• When I do IFR training approaches I always choose the option of a low approach at minimumS (so basically a go-around): The idea behind that is
  • being confident wit the aircraft's behavior when initiating the go around with the aircraft in full landing configuration
  • having the option of going-around at minimum/DH being "burned" into my brain at the very top of the options list for the decision making process. 

Procedure (very much standard)

• After reading the approach check list, typically when flying the leg to the I,F I disengage the A/P to get used to hand-flying and start a "real" instrument scanning process.
• When intercepting final track reducing speed to 110IAS (if not advised otherwise)
• Once established flaps in T/O position, gear down at FAP/FAF, 105IAS
• When approaching short final (OM or Check Altitude position 3-4NM before threshold), check altitude, full configuration, final check list, reduce to 85IAS
• 100ft above DA "approaching minimum" call out,
• at DA, decide to go around (full power, 8-10° nose up attitude, speed check, flaps T/O, gear up, flaps up, trim, engage A/P, call radar, ..) or reduce to 75KIAS or lower for visual approach

If there is a risk to get behind the airplane / being overwhelmed by the conditions, I would certainly use the A/P to reduce work load!
However, I want to stay proficient in hand-flying and with the SVT-FPM it is really easy (for training purposes I sometimes turn of the SVT option, very seldom).
Disclaimer: - just an engineer, not an FI - 

Best,
Matthias

Minor things I added to the initial post: 

• The G1000 is WAAS enabled
• I debrief all flights and approaches using CloudAhoy
• I monitor engine status using Savvy

Edited May 28, 2023 by MatthiasArnold
minor additions

[midlifeflyer]

20 hours ago, Deb said:

As Greg posted, it’s in the POH supplement:

 

If it's a limitation for the installation in your aircraft, that's exactly where it is gonna be,

[jlunseth]

Normally, if flying an approach to landing in actual, I let the autopilot take the aircraft down to minimums or field visibility, whichever comes first. I would not change control in the middle of an approach, not in actual. When training in VFR or under the hood I will change control and will hand fly approaches just to train for the possibility that the AP does something kinky someday in actual. I have had things like that happen but usually not the AP, in one or two instances I have had to switch to flying an LOC rather than an ILS because for whatever reasons the AP failed to couple, or something similar with an RNAV type approach, maybe the GPS won’t allow an LPV. But that is training. I prefer not to change control in IMC in order to keep things stable and keep me focused.

[Steve Yucht]

Like Matthias above I only hand fly past the FAF.  Without a doubt my approaches are not as smooth as the autopilot but I personally feel very comfortable doing this.  If there was a problem with your AP and you suddenly had to hand fly after the FAF things could get crazy or dangerous.  I would rather have my mindset totally committed to hand flying.  This keeps my proficiency up for sure.  My approach: drop gear 1 mi outside the FAF or 1.5 mi if bombing in per ATC request to keep speed up.  AP off and first notch of flaps at final.  Ride down the glideslope starting out at 100 kts and slowly using small pitch and power changes to get to 85 kts 500 fpm descent calling out altitude and DA/MDA every 100 ft (I have practiced slower but in real weather particularly gusting wind I like the safety of airspeed and find I have plenty of time to slow down even breaking out at minimums). I typically don't bother adding final flaps unless I know the runway is relatively short. Coming out of the soup at minimums who cares if you float 500 feet as long as you don't go off the end. 

Big proponent of hand flying to keep proficient but if you don't do it regularly I suspect using the AP to mins would be safer. 

Edited June 3, 2023 by Steve Yucht