Retract Gear or Flaps First in a Go Around ?

[EricJ]

16 hours ago, Ibra said:

That's posh  I think others answered the question on "vario" 

Finding a new analogue one would be expensive. 

I think Garmin PFD (e.g. G5, GI275) process static input and give a sort of  "instantaneous vertical speed  reading"? 

I've noticed that, that the G5 VSI is pretty responsive compared to the air VSI instrument.   I've adapted to using it more as it does seem pretty useful.   I also fly G1000 aircraft and haven't really paid much attention to the responsiveness of the VSI in that system.   I'll likely be more attentive to it just to see the difference.

[PeteMc]

16 hours ago, Ibra said:

I think Garmin PFD (e.g. G5, GI275) process static input and give a sort of  "instantaneous vertical speed  reading"? 

I found a reference to an IVSI in the GI275 manual, but it seems to be associated with TCAS II.  So I wonder if it is available for GA or you need a different version of the 275. 

[rturbett]

I practiced today with a few go arounds- 1980 M20J. Retracting the gear had a much less affect on the trim than flap retraction.  I'll be a pull the gear up first pilot.

[hazek]

3 hours ago, rturbett said:

I practiced today with a few go arounds- 1980 M20J. Retracting the gear had a much less affect on the trim than flap retraction.  I'll be a pull the gear up first pilot.

Did you maybe try retracting flaps to flaps T/O followed by immediately with gear up for comparison? Would be cool to have that data point.

[Pinecone]

On 8/30/2025 at 11:27 AM, Jackk said:

There is a reason why industry wide “positive rate grear up”

 

and flaps gear flaps 

is a thing 

 

I’d think a Mooney would be the same 

Hmm, T-37. T-38, A-10 are all Gear Up then Flaps up on go arounds.  SO flaps/gear/flaps is NOT industry wide.

If flaps and gear have similar drag, I am going to retract gear first as it is all drag.  Flaps are lift also.

If I had a flap system that I could set a flap setting, not holding a switch in timing, I might consider your method.

[Pinecone]

On 8/30/2025 at 1:00 PM, Hank said:

A quick glance at my IVSI will confirm that it's safe to reach for the gear switch. I usually talk out loud while doing this.

I was taught Up on VSI AND Up on Altimeter, THEN retract gear.

[gabez]

I always pitch up, gear up, flaps up that's what the POH says 

[Pinecone]

2 hours ago, gabez said:

I always pitch up, gear up, flaps up that's what the POH says 

You should confirm climb before gear up.

Pitch up does not always mean go up.

[gabez]

1 hour ago, Pinecone said:

You should confirm climb before gear up.

Pitch up does not always mean go up.

that's what I meant...so yes we are in agreement 

[dkkim73]

On 8/30/2025 at 11:54 PM, MikeOH said:

I believe there is a movable (vertically) weight rigged to a bellows of sorts.  When you climb or descend the force of vertical acceleration compresses or expands the bellows and provides an instantaneous increase/decrease of pressure vs. the delay caused by the calibrated leak in the case.

It is really is inertial nav, if you think about it. Fishing weight instead of fancy laser ring gyro...

[MikeOH]

1 minute ago, dkkim73 said:

It is really is inertial nav, if you think about it. Fishing weight instead of fancy laser ring gyro...

LOL!

Yes, definitely making use of F=Ma

[dkkim73]

On 8/31/2025 at 6:08 PM, EricJ said:

I've noticed that, that the G5 VSI is pretty responsive compared to the air VSI instrument.   I've adapted to using it more as it does seem pretty useful.   I also fly G1000 aircraft and haven't really paid much attention to the responsiveness of the VSI in that system.   I'll likely be more attentive to it just to see the difference.

IIUC most of these units have at least a primitive MEMS(?) AHRS, not a full independent longer-timeframe INS, but that should be enough to come up with a nice simulation of mechanical IVSI behavior, wouldn't you think? 

[dkkim73]

2 minutes ago, MikeOH said:

LOL!

Yes, definitely making use of F=Ma

Well, one of the several, if unpaid, uses of a physics education is things like this...

 

[EricJ]

11 minutes ago, dkkim73 said:

IIUC most of these units have at least a primitive MEMS(?) AHRS, not a full independent longer-timeframe INS, but that should be enough to come up with a nice simulation of mechanical IVSI behavior, wouldn't you think? 

It's better than a primitive AHRS, since it provides the AI function for use in certificated aircraft.   It also has awareness of GPS location and the pitot and static air inputs.  So, yeah, one would think it'd have the capability to sort out a decent VSI. 

[N201MKTurbo]

All you need to get a VSI is the altitude. All you have to do is integrate the altitude signal over time. It kind of depends on the update rate of the A/D converter. The shortest time you can integrate is two samples at the ADCs sample rate. That would almost certainly be very noisy. So you need to integrate over a longer time to get a stable reading. This can make the indication lag. So you have to pick a time span that is a good compromise between noise and lag. You could sum it with the output of the vertical component of the accelerometer to speed it up some. Everything is a compromise. You just have to come up with a solution that meets the requirements. Whatever they come up with, it will be better than a mechanical VSI.

[jamesm]

A question on sequencing on a Go Around  (for a manual C model sorry I am the wrong forum). So doing  some  instrument training an instructor found it odd that I would raise the gear first before applying power (Throttle). The flaps I never extend flaps just place the flap diverter valve lever to down (Manual flaps 100MPH limit). Is this bad habit on my part? or?

 

Thanks bring this topic up,

James 67C

 

[201Mooniac]

2 hours ago, N201MKTurbo said:

All you need to get a VSI is the altitude. All you have to do is integrate the altitude signal over time. It kind of depends on the update rate of the A/D converter. The shortest time you can integrate is two samples at the ADCs sample rate. That would almost certainly be very noisy. So you need to integrate over a longer time to get a stable reading. This can make the indication lag. So you have to pick a time span that is a good compromise between noise and lag. You could sum it with the output of the vertical component of the accelerometer to speed it up some. Everything is a compromise. You just have to come up with a solution that meets the requirements. Whatever they come up with, it will be better than a mechanical VSI.

Sorry to ask but do you mean differentiate the altitude to get the rate of change of altitude or am I not understanding what you are after?

[MikeOH]

26 minutes ago, 201Mooniac said:

Sorry to ask but do you mean differentiate the altitude to get the rate of change of altitude or am I not understanding what you are after?

You beat me to it!

You would differentiate altitude to get VSI (time rate of change of altitude)

[N201MKTurbo]

19 minutes ago, 201Mooniac said:

Sorry to ask but do you mean differentiate the altitude to get the rate of change of altitude or am I not understanding what you are after?

So, you are correct. I usually think of averaging things over time and dividing by the number of samples, like the I term of a PID controller. But we are looking for the rate of change. So we have to look at the difference over a number of samples. It gets interesting trying to filter a differential signal.

[EricJ]

35 minutes ago, N201MKTurbo said:

So, you are correct. I usually think of averaging things over time and dividing by the number of samples, like the I term of a PID controller. But we are looking for the rate of change. So we have to look at the difference over a number of samples. It gets interesting trying to filter a differential signal.

Differentials/derivatives tend to be noisier than the original signal, too, so it does get tricky.   It does seem reasonable to expect to be able to augment the air data VSI with GPS and/or accelerometer data, though and decrease the delay.

[Raistlin]

For what it’s worth (I still have few hours in my Bravo) I also found it better to change pitch and add power, confirm I am climbing and then raise gear before flaps.

After all, we usually do gear-flaps-flaps on approach (instead of flaps-gear-flaps on many other aircraft), so in my mind it just makes sense to do it in reverse.

At least once, doing a balked landing at very low speed initially, I found it necessary to accelerate in ground effect, and instinctively raised gear while doing so. I still think that was a mistake (even if it all worked fine).

The entire maneuver is very intense so a flow definitely helps.

Edited Wednesday at 07:40 AM by Raistlin

[PeteMc]

5 hours ago, jamesm said:

A question on sequencing on a Go Around  (for a manual C model

So how fast do you shoot the Approach?  I got to fly a manual gear Mooney from NY down to FL one time.  I get what people say about getting the gear up while you're still slow.  So I could see wanting to get the gear up pending what your speed already is and if you're already getting close to the hard-to-retract speed. 

And it might mess me up if I swiched up my process.  But if it is the way you always do it, my guess is you're process is as safe as mine. 

[hazek]

Not that I think highly of the Bravo POH, it's dogshit actually. But would be cool to know what their reasoning was for prescribing the go around procedure to be flaps gear flaps. Anyone know?

[Pinecone]

11 hours ago, jamesm said:

A question on sequencing on a Go Around  (for a manual C model sorry I am the wrong forum). So doing  some  instrument training an instructor found it odd that I would raise the gear first before applying power (Throttle). The flaps I never extend flaps just place the flap diverter valve lever to down (Manual flaps 100MPH limit). Is this bad habit on my part? or?

James 67C

I agree with your instructor.  Power first.  Confirm climb, THEN raise gear.

[1980Mooney]

Complicating this discussion is the fact that prior to 1987 (24-3000), M20J's did not have a "take-off" preselect on the flaps.  I think it is the same with the M20K but have not looked at all the wiring diagrams. Late J's & K's and Long Bodies have the takeoff preselect.

The POH states that if balking a landing with full flaps deployed the pilot should Retract the flaps to "take-off" position before Retracting Landing Gear and then fully Retracting Flaps (from "take-off" position to 0 degrees). This means that the pilot has to look down at the indicator while toggling the flap switch and watch until it centers at the "take-off mark.  This fumble farting around looking down can spell disaster when forced to execute a go-around while trying to land possibly in the clag or with an animal popping out on the runway.

@PT20J and others are right that full flaps deployed while landing can provide maximum landing performance (except in some conditions like strong winds, etc) but the lack of take-off flap preselect on most "modern" Mid-Bodies creates a sub-optimal (I would argue unsafe) situation to be dancing "flaps, gear, flaps" during a forced go-around.

I think it better in Mooney's without a "takeoff" flap preselect to compromise and set up to land with "take-off" 15-degree flaps.  That way you are set up to go around without thinking about it - without having to fumble/bumble looking down at a hard to see indicator (especially at night) to raise from Full Flaps to the Take-off Flaps mark on the indicator before raising Landing Gear.  If set up with "take-off" flaps, once you break out or know the runway is clear, you can throw in the remaining flaps with a single press of the flap actuator switch (and not having to look) if you think it is needed.

Everything in aviation is a compromise.  I have no idea why Mooney did not have a "take-off preselect" or a stepped flaps actuator (like all Cessna) all along.   Just my 2 cents.

Edited Wednesday at 11:12 PM by 1980Mooney