IFR Departure - my new SOP

[Yariv]

Hi all,

I am pretty new to flying with G1000 and GFC700 (since last May) but have learned a lot during the last 7 months, some from CFIIs and some on my own. The new procedure I describe below falls into the latter category:-).

Background:

IFR departure, especially when it is low ceilings, is a very busy time for the pilot. One of the tasks I try to accomplish early during the departure is to engage the autopilot. I found it really distracting to press the AP, then get it off the default settings of Roll and Pitch to the proper settings of Hdg (or Nav) and climb to target altitude using FLC (push nose down to the right airspeed).

So I modified this process to: I press the FD first, set the mode to Hdg and Climb using FLC, adjust the airspeed to 120 Kts, and only then I press AP.

My new process:

I thought I would make the process even more efficient by doing all this FD button pressing on the ground as part of the run up and then all that's left for me to do is press the AP once I finish the take off run and gain a few hundreds of feet. I tested it yesterday and it worked exactly as I expected it to work.

To summarize, here is the flow: at the end of my runup I configure the Flight Director and GFC700 as follows - (example figures from Paine 6 departure at Paine field, KPAE)

1. Press FD
2. set target altitude to 2000'
3. press Hdg and set heading bug to 163 degrees
4. press FLC and set climb airspeed to 120 Kts using the push nose down

I would be interested to hear what procedures other more experienced pilots use. Also, do you see any flaws with the process I describe?

Thank you,

Yariv

 

[ilovecornfields]

I have a KFC 225 so I can't comment on the GFC 700. For mine, I put in in FD mode, HDG/GPSS, altitude arm at the cleared initial altitude and 1300 FPM climb (I'll do 1000 FPM if my son is with me because he complains every time the VSI goes past 1000. He will point to the VSI and give me a "thumbs down" and frowny face. Without fail.). 

When I takeoff I go immediately to the instruments. Positive rate - gear up, 85 KIAS - flaps up, then AP on. I assume there's a minimum altitude approved for the AP but I don't want to know what it is (bonus points if you can name which "Hazardous Attitude" this is an example of).

This helps cut down on the workload. I try to hand fly the departures at least once or twice a month just to convince myself I can do it.

I'm not very familiar with the Paine 6 Departure. Is 2000 the initial altitude they usually clear you to? I also don't have FLC. Not sure if it's better to initially set a ROC or airspeed. If you forgot to retract the speedbrakes, gear or flaps which mode would get you in trouble faster?

[Yariv]

The choice to use FLC (flight level change) was recommended to me by the previous corporate pilot who flew this airplane. It makes sense to me as well - if the airplane is at 120 (or 110) during the initial climb then you don’t need to worry about stall or getting close to a stall as opposed to VS (vertical speed) mode.

[ilovecornfields]

6 minutes ago, Yariv said:

The choice to use FLC (flight level change) was recommended to me by the previous corporate pilot who flew this airplane. It makes sense to me as well - if the airplane is at 120 (or 110) during the initial climb then you don’t need to worry about stall or getting close to a stall as opposed to VS (vertical speed) mode.

Agreed. But if there's a mountain in the way you may need that ROC...

I think it depends on where you are and what you're worried about. If you forget one of those items are you likely to notice the low airspeed or low ROC first? Again, I don't have FLC so not even an option for me but I keep a pretty close eye on that airspeed and if it started creeping down (or I heard the stall horn) it would probably get my attention quickly. I agree if there's no terrain around FLC may be a better choice.

I have a friend who was sitting right-seat in a Pilatus that was climbing in FLC mode and forgot to raise the flaps.  He commented to the pilot "that's funny, the other pilot doesn't usually leave the flaps down the whole time we're climbing."

One of my instructors liked me to say "gear up, flaps up, engine instruments green" before engaging the AP. I don't think that's a bad idea either.

[Yariv]

Yes, I agree with your priority list: first clean the airplane then engage the autopilot. And yes, if a predetermined climb gradient is required then VS mode is more appropriate. In Paine field there are no obstructions on takeoff and the initial altitude in the SID is 2000’.

[Danb]

Very recently I did similar in a 500 ovc and engaged ap just prior to entering the clouds, my G1000 has the STEC, Inset the alt to 2000 ft. I suddenly had the plane pitch down, I didn’t get it under control until about 20-30 feet from runway. Closest I’ve been to buying the farm..I subsequently changed my procedure to not turning on the ap until I have complete control at around 800-1000 ft. Last few takeoffs were uneventful thank god. I’m still not sure why this occurred but am pretty sure. On the stec make sure the ROC is in the + not - even though you’ve entered the target altitude say 2000. In the few seconds just before hitting almost the ground I attempted to do the normal stuff disengage vis trim switch, turn off autopilot etc, I ended overpowering the plane. Fran stated we just missed the fence.. we’re not entitled to make mistakes they do accumulate. Be safe

 

[jaylw314]

17 minutes ago, Yariv said:

Yes, I agree with your priority list: first clean the airplane then engage the autopilot. And yes, if a predetermined climb gradient is required then VS mode is more appropriate. In Paine field there are no obstructions on takeoff and the initial altitude in the SID is 2000’.

I have no idea about the GFC700 stuff, but, I'd point out the 2000' MSL on the Paine 6 is not relevant for navigation, you should just dial in your assigned altitude.  The 2000' MSL just marks the point at which you need to have HEARD from ATC before planning on lost comms, which would be continuing your climb to assigned altitude, so there's no point setting an initial altitude at 2000' and then changing it to your assigned, just go ahead and set it as your assigned altitude.  One less thing to do in the soup

If ATC calls and changes your altitude restriction, all your careful planning will go out the window anyway  

[PT20J]

46 minutes ago, ilovecornfields said:

I assume there's a minimum altitude approved for the AP but I don't want to know what it is (bonus points if you can name which "Hazardous Attitude" this is an example of).

I'm curious what drives your thinking here since you admit to knowing a limitation exists, have made a conscious decision to ignore it, and have self-identified that as hazardous attitude.

I'm not criticizing you. I have noticed in your posts that you are a thoughtful person, and so I'm genuinely curious about the motivation behind the decision. I doubt you would purposely exceed gear and flap airspeed limitations. So, why is the autopilot (which, of course, will try to kill you if it goes haywire or you set it up incorrectly) different?

(BTW, the altitude is 800' and it found in the limitations section in Mooney KFC 225 AFMS)

Skip

[Yariv]

42 minutes ago, jaylw314 said:

I have no idea about the GFC700 stuff, but, I'd point out the 2000' MSL on the Paine 6 is not relevant for navigation, you should just dial in your assigned altitude.  The 2000' MSL just marks the point at which you need to have HEARD from ATC before planning on lost comms, which would be continuing your climb to assigned altitude, so there's no point setting an initial altitude at 2000' and then changing it to your assigned, just go ahead and set it as your assigned altitude.  One less thing to do in the soup

If ATC calls and changes your altitude restriction, all your careful planning will go out the window anyway  

If I am assigned the Paine 6 departure, then as filed, then 2000’ is very relevant. Once in contact with the approach control and they assign a different altitude it is very easy to dial the new altitude and continue the climb. Climbing to 2000’ from a field elevation of 600’ happens really fast. It is a good thing to have the climb stop there, even if it is temporary until I get the new assigned altitude. 

[jaylw314]

Do they often assign 2000' or lower as an initial altitude? Obviously, then you'd set the assigned altitude.

If they assign higher, say, 3000' on your IFR clearance, then you're not supposed to stop at 2000' unless that was part of your clearance or if you then get an instruction to the contrary from ATC.  If they don't respond until you reach 2000', the SID instructs you to continue the climb to 3000'.  Either way, you're climbing to the assigned altitude.

In other words, I can't see a reason to preset an altitude on the autopilot to anything other than the assigned altitude.   You don't want to level off at 2000' since ATC isn't expecting it (unless, of course, that's actually the assigned altitude).

It may be easy to change altitudes on the autopilot, but you were asking about anything that would decrease your workload

[ilovecornfields]

54 minutes ago, PT20J said:

I'm curious what drives your thinking here since you admit to knowing a limitation exists, have made a conscious decision to ignore it, and have self-identified that as hazardous attitude.

I'm not criticizing you. I have noticed in your posts that you are a thoughtful person, and so I'm genuinely curious about the motivation behind the decision. I doubt you would purposely exceed gear and flap airspeed limitations. So, why is the autopilot (which, of course, will try to kill you if it goes haywire or you set it up incorrectly) different?

(BTW, the altitude is 800' and it found in the limitations section in Mooney KFC 225 AFMS)

Skip

Hi Skip,

Thank you for caring enough to call me out on that and for looking up the altitude restriction (I actually thought it was 400’). I think you’re certainly justified in criticizing me for it. To be honest, it’s a situation that challenges me a little bit because I don’t really know what the safest thing to do is when taking off in low IFR conditions. 
I get frustrated sometimes with the overlap of safe vs. legal and feel that we often focus more on what is legal than what is safe. The Learjet at SEE could legally cancel IFR and enter the pattern for 27 R but it clearly wasn’t safe. I’ve listened to the recording a few times and it’s kind of eerie the moment you realize their fate was sealed when they made the very legal decision to cancel IFR and proceed VFR (ironically it would have been much safer to proceed straight-in and land on the shorter runway, but perhaps not legal).

I’ve read a lot of accidents where pilots take off in low IFR, get disoriented and crash - often never reaching 800’. Would they be alive today if they had “illegally” engaged the autopilot sooner? How do you balance those experiences with those of people like @Danb who almost died by engaging the autopilot down low. Which one is more likely to kill me? I honestly don’t know.

When I engage the autopilot I’ve already had it in FD mode so unless I do something really dumb it should be pretty predictable. I’ve always tested the AP disconnect during preflight and keep my hand on the yoke and the finger over the button so hopefully I would be able to intervene quickly if it went on a suicide mission. 

The FAA tells me the antidote is “follow the rules, they are usually right” but I don’t love that answer because sometimes they’re not. The toxicologists love to say “the dose makes the poison” and I kind of agree with them with respect to those attitudes. I think sometimes when you have an issue with safe vs. legal the smart move is to go with safe but I feel too often people focus on “legal.” Most of the time there’s a huge overlap, but sometimes you have to pick one over the other. There are lots of ways to legally get killed in an airplane.

I probably should have phrased what I said in a better way. Maybe I’m just tired. I just worked 3 days in challenging conditions dealing with the virus that shall not be named and people trying to legislate behavior and I’m kind of frustrated with the emphasis on what is legal instead of what is safe and prudent. Sorry if I’m taking it out on you guys.

I appreciate you caring enough to challenge me on it.

[PT20J]

One thing I noticed for myself is that the modern avionics are so capable that it is easy to get over dependent on them. Who hasn't had a moment (or two) of confusion when getting an unexpected clearance  and fumbling around trying to get the automation programmed? And, it's easy to feel that we aren't proficient (and perhaps we aren't) at hand flying when we use the autopilot most of the time. I don't find it difficult to go from hand flying to engaging the autopilot, but I find it more challenging to go the other way because I don't scan the attitude as intently when monitoring the automation as I do when hand flying and it takes a fairly intense period to get back in the groove.

FAA aside, I think deciding when to engage the autopilot on a low ceiling IFR departure involves a bit of risk assessment. The KFC 225 AFMS lists 340' as the max deviation during a failure in cruise, climb or descent. Perhaps they rounded up to 400 and doubled it to get 800'. Elsewhere the document discloses that the autopilot will disengage if it sees a pitch rate of 6 deg-sec. That's quite a bit. So clearly there are some failure modes that would be dicey. Thus, I think it comes down to a simple calculation: Do I want to bet my life that the autopilot won't go bonkers and kill me, or do I want to trust that I am proficient enough to fly the airplane without the autopilot?

I think probably everyone has flown when they were feeling less than 100% proficient. If you don't fly for a living it's hard to stay proficient in instrument flying, crosswind landings, night flying, etc. We just don't have enough opportunities to experience all those conditions. So, I think an occasional over reliance on the automation is just going to happen if I want to get maximum utility from the airplane. But, it always makes me a bit uncomfortable. 

Anyone else have some thoughts?

Skip

[Yariv]

1 hour ago, jaylw314 said:

Do they often assign 2000' or lower as an initial altitude? Obviously, then you'd set the assigned altitude.

If they assign higher, say, 3000' on your IFR clearance, then you're not supposed to stop at 2000' unless that was part of your clearance or if you then get an instruction to the contrary from ATC.  If they don't respond until you reach 2000', the SID instructs you to continue the climb to 3000'.  Either way, you're climbing to the assigned altitude.

In other words, I can't see a reason to preset an altitude on the autopilot to anything other than the assigned altitude.   You don't want to level off at 2000' since ATC isn't expecting it (unless, of course, that's actually the assigned altitude).

It may be easy to change altitudes on the autopilot, but you were asking about anything that would decrease your workload

By the way, this is a bit of a sidetrack from my main subject which was configuring the Flight Director before takeoff and then just engaging the autopilot later in the departure. You are discussing the details from the example I used, Paine 6 departure. So to address your questions/comments, ATC never assigns an initial altitude of less than 2000' at Paine field. This SID is a radar controlled SID, the final altitude is assigned by ATC after you are switched from the Tower to them. Typically, they leave you at 2000' for a minute or so, they may turn you away from Seattle (250 degrees) and then climb you further to the final altitude. You cannot climb to your final altitude before they tell you so. Of course, if you are switched to them while still climbing to 2000' (say you are at 1700') and then tell you "climb 3000' turn right 250, then you continue your climb and turn. If your clearance says - clear to KPWT, via Paine 6 departure, then as filed, climb 2000' - then you stop at 2000'. My filed altitude was 4000'. In this case they did assign an altitude in the clearance. But sometimes they just mention the SID, and add "expect 4000' 5 minutes after departure". And yes, in lost communication case we are expected to proceed to our assigned altitude.

[jaylw314]

3 minutes ago, Yariv said:

By the way, this is a bit of a sidetrack from my main subject which was configuring the Flight Director before takeoff and then just engaging the autopilot later in the departure. You are discussing the details from the example I used, Paine 6 departure. So to address your questions/comments, ATC never assigns an initial altitude of less than 2000' at Paine field. This SID is a radar controlled SID, the final altitude is assigned by ATC after you are switched from the Tower to them. Typically, they leave you at 2000' for a minute or so, they may turn you away from Seattle (250 degrees) and then climb you further to the final altitude. You cannot climb to your final altitude before they tell you so. Of course, if you are switched to them while still climbing to 2000' (say you are at 1700') and then tell you "climb 3000' turn right 250, then you continue your climb and turn. If your clearance says - clear to KPWT, via Paine 6 departure, then as filed, climb 2000' - then you stop at 2000'. My filed altitude was 4000'. In this case they did assign an altitude in the clearance. But sometimes they just mention the SID, and add "expect 4000' 5 minutes after departure". And yes, in lost communication case we are expected to proceed to our assigned altitude.

I think I see what you're saying, when you mentioned to set your altitude to 2000', it was because that happened to be your initial assigned altitude, not anything related to the SID.

FWIW, using a KFC150, I fly by hand until I've completed the first turn, whenever that is, so I set the heading bug to my first heading after the runway.  It means I don't have to depend on the autopilot until I'm sure I'm away from the ground, done my climb checklist and heading in the right direction, then I can just turn on the AP.  If I get new instructions from ATC before I'm there, I just use the heading bug and altitude selector as my notepad.

 

[Ragsf15e]

29 minutes ago, Yariv said:

By the way, this is a bit of a sidetrack from my main subject which was configuring the Flight Director before takeoff and then just engaging the autopilot later in the departure. You are discussing the details from the example I used, Paine 6 departure. So to address your questions/comments, ATC never assigns an initial altitude of less than 2000' at Paine field. This SID is a radar controlled SID, the final altitude is assigned by ATC after you are switched from the Tower to them. Typically, they leave you at 2000' for a minute or so, they may turn you away from Seattle (250 degrees) and then climb you further to the final altitude. You cannot climb to your final altitude before they tell you so. Of course, if you are switched to them while still climbing to 2000' (say you are at 1700') and then tell you "climb 3000' turn right 250, then you continue your climb and turn. If your clearance says - clear to KPWT, via Paine 6 departure, then as filed, climb 2000' - then you stop at 2000'. My filed altitude was 4000'. In this case they did assign an altitude in the clearance. But sometimes they just mention the SID, and add "expect 4000' 5 minutes after departure". And yes, in lost communication case we are expected to proceed to our assigned altitude.

What matters (usually) for setting your altitude is in the clearance you wrote down before takeoff and/or any amendment given by tower before takeoff.  So if you use CRAFT (clrnc fix, route, ALT, frequency, transponder) to write down your clearance, then that Altitude is generally what you want set.  If tower gives you a different altitude prior to departure, then set that.  

[Danb]

1 hour ago, jaylw314 said:

I think I see what you're saying, when you mentioned to set your altitude to 2000', it was because that happened to be your initial assigned altitude, not anything related to the SID.

FWIW, using a KFC150, I fly by hand until I've completed the first turn, whenever that is, so I set the heading bug to my first heading after the runway.  It means I don't have to depend on the autopilot until I'm sure I'm away from the ground, done my climb checklist and heading in the right direction, then I can just turn on the AP.  If I get new instructions from ATC before I'm there, I just use the heading bug and altitude selector as my notepad.

 

That’s generally exactly what I do, the one time I engaged early reinforced me to stay with my normal procedures. Couldn’t agree more with Skip, the reason for my post was to highlight one should not alter there procedures 

[M20F-1968]

4 hours ago, Danb said:

Very recently I did similar in a 500 ovc and engaged ap just prior to entering the clouds, my G1000 has the STEC, Inset the alt to 2000 ft. I suddenly had the plane pitch down, I didn’t get it under control until about 20-30 feet from runway. Closest I’ve been to buying the farm..I subsequently changed my procedure to not turning on the ap until I have complete control at around 800-1000 ft. Last few takeoffs were uneventful thank god. I’m still not sure why this occurred but am pretty sure. On the stec make sure the ROC is in the + not - even though you’ve entered the target altitude say 2000. In the few seconds just before hitting almost the ground I attempted to do the normal stuff disengage vis trim switch, turn off autopilot etc, I ended overpowering the plane. Fran stated we just missed the fence.. we’re not entitled to make mistakes they do accumulate. Be safe

 

As I was reading this thread my first thought is why are others engaging the autopilot so close to the ground.  When take off I want to be in control of the airplane in as simple and reliable a manner as possible.  I think that means hand fling the airplane without concerns of buttons and electronic that can fail, or at a minimum cause unwanted diversions.  I would not fuss with the autopilot until I am at least 1000 ft above the ground, or likely more.  Am I missing something?

John Breda

[Brent]

3 hours ago, PT20J said:

One thing I noticed for myself is that the modern avionics are so capable that it is easy to get over dependent on them. Who hasn't had a moment (or two) of confusion when getting an unexpected clearance  and fumbling around trying to get the automation programmed? And, it's easy to feel that we aren't proficient (and perhaps we aren't) at hand flying when we use the autopilot most of the time. I don't find it difficult to go from hand flying to engaging the autopilot, but I find it more challenging to go the other way because I don't scan the attitude as intently when monitoring the automation as I do when hand flying and it takes a fairly intense period to get back in the groove.

FAA aside, I think deciding when to engage the autopilot on a low ceiling IFR departure involves a bit of risk assessment. The KFC 225 AFMS lists 340' as the max deviation during a failure in cruise, climb or descent. Perhaps they rounded up to 400 and doubled it to get 800'. Elsewhere the document discloses that the autopilot will disengage if it sees a pitch rate of 6 deg-sec. That's quite a bit. So clearly there are some failure modes that would be dicey. Thus, I think it comes down to a simple calculation: Do I want to bet my life that the autopilot won't go bonkers and kill me, or do I want to trust that I am proficient enough to fly the airplane without the autopilot?

I think probably everyone has flown when they were feeling less than 100% proficient. If you don't fly for a living it's hard to stay proficient in instrument flying, crosswind landings, night flying, etc. We just don't have enough opportunities to experience all those conditions. So, I think an occasional over reliance on the automation is just going to happen if I want to get maximum utility from the airplane. But, it always makes me a bit uncomfortable. 

Anyone else have some thoughts?

Skip

I had no issue engaging my S-TEC 30 in the clouds on departure because I knew (er, 90% knew) what it was going to do. But I'm pretty cautious with a new GFC 500 (no IMC for me until I have that and the other new stuff down cold). I had an instructor once who said autopilots are like student pilots - you have to watch them every second. And the first few times I hit the "AP" button on this new GFC 500, the plane often went somewhere I didn't expect, usually up or down because of the slick altitude selection modes that I wasn't used to.   

[carusoam]

One of the critical things left out of the autopilot conversations….

Our APs are capable and authorized to put us really close to the ground for landing…

Yet they often are not allowed to be used until at 800’ agl… 

 

When descending, we have plenty of time to make sure the AP is doing what we expect… if it automatically starts to climb, or descend or change altitudes… we arrest it’s behavior… and we may be off a few hundred feet if caught quickly…

Every time there is a change to the operation… the computer (often old and slow, and attached to servos that are worn) decides what is needed to follow the course…

If we press the wrong button, nav vs. hdg or something like that… we have a few minutes to figure out that there is a problem…

Or if a servo motor decides it doesn’t want to operate properly…. We will notice the dolphin like behavior….

 

So…

Coming off the ground and going to AP on…. Leaves you very responsible to make sure the AP is doing what you asked it to do….   Check your performance numbers… climbing? On course?…. Then check again to make sure it wasn’t just momentary….

Expect that the AP won’t behave….

 

Lets face it…. Coming down from altitude… everything is operating from a steady state…. And will probably maintain that state to the ground…

Leaving the ground… it is the opposite condition… we won’t hit steady state until gear is up, flaps are up, and trim has been adjusted….  Which is a bit of a challenge to get accomplished a few hundred feet off the ground….

Especially if you are climbing out a 2kfpm….  (24 seconds to get to 800’ agl…)

 

So… again….

If you turn the device on for assistance… continuous monitoring is best to keep to keep things going the right direction…

 

How long do you need to wait to know YOUR AP is behaving properly?

 

Looks like this both a human challenge and a hardware challenge…

 

I liked having the clouds at TPA or above….  Solely because the airplane can be set up in a steady state before going on the instruments…

Time is flying by… you need to know your instruments are working at the same time…. And engine instruments are in the green… FF matches expectation…

Steady state is everything….  
 

PP thoughts only, 

-a-

[donkaye]

7 hours ago, ilovecornfields said:

If you forgot to retract the speedbrakes, gear or flaps which mode would get you in trouble faster?

Gear, Speedbrakes, Flaps in that order.  This assumes it is not a go-around, but a normal takeoff.

[Ethan]

I have the GFC 500 in my Mooney 231. Before departing IFR, I set the top altitude in my altitude preselect window on my G5. Just before taking the runway after my take-off clearance, I push the TOGA button that activates the FD, 7 degrees nose up, then I set my heading bug to the runway heading which then commands a turn to the Runway heading. When I line up on the runway, the command bars are 7 degrees up but indicate no turn. I then add power and rotate by smoothly pitching-up into the FD command bars. Through 400 feet AGL, I push NAV so the FD will indicate the turns on the departure procedure. I then set the pitch mode to IAS and dial in 96 KTS (VY) with the speed wheel. After I am sufficiently high, I may engage the autopilot, but I do enjoy hand flying so usually just continue hand flying. The FD makes zero/zero takeoffs less stressful just because the flight director paints the desired pitch and heading right onto the attitude indicator.

[carusoam]

The FD is pretty nice at letting you know what the computer has in mind… in the moment….

Without command bars… the AP is pretty much keeping it a secret….  
 

-a-

[PT20J]

8 minutes ago, carusoam said:

The FD is pretty nice at letting you know what the computer has in mind… in the moment….

Without command bars… the AP is pretty much keeping it a secret….  
 

-a-

It might be a little more complicated in a GFC 500. The FD software is in the PFD but the autopilot software is in the servos. They talk via the CAN bus, but we cannot hear what they are saying 

 

[MB65E]

For sure!! The Around the horn flight modes set up is a big help. The flow in our Falcon May help. The PFD call outs are Speeds posted, airspeed Zero, set to 190kts (bug), HDG,FMS1,Pitch, ALTS, ASEL set. Alt checks 3 times, baro set 3 times times, RAD alt 0, HDG checks 5 times, and HDG set. 
Sounds like a lot but one can rattle it off quickly. 
I wish was a better training environment to tie in GA stuff to instrument flying. I kinda struggled transitioning to corporate flying. There is not a lot that prepares you. 
 

-Matt
 

 

[Will.iam]

7 hours ago, PT20J said:

I'm curious what drives your thinking here since you admit to knowing a limitation exists, have made a conscious decision to ignore it, and have self-identified that as hazardous attitude.

I'm not criticizing you. I have noticed in your posts that you are a thoughtful person, and so I'm genuinely curious about the motivation behind the decision. I doubt you would purposely exceed gear and flap airspeed limitations. So, why is the autopilot (which, of course, will try to kill you if it goes haywire or you set it up incorrectly) different?

(BTW, the altitude is 800' and it found in the limitations section in Mooney KFC 225 AFMS)

Skip

I have the kfc-150 autopilot system not the 225 but I can’t imagine it would have a a more restrictive limitation than mine. Having said that i do not have an autopilot altitude limitation for engagement. I do have a chart for autopilot malfunction that shows the maximum loss of altitude of 400ft so it would be prudent to be above that altitude just in case the autopilot decided to go crazy and i needed to take control back and worse case i would lose 400ft in the process. I also hace the 297 altitude pre-selector and it does have a limitation of not setting an altitude lower than 800ft agl but that is a limitation on the pre-select not on the autopilot, 2 very different things. So as long as you set your level off alt to 900ft agl or above you can engage your autopilot right after takeoff if you feel lucky that it will not malfunction or wait until 400 ft if you are an expert pilot at upset recovery or wait to some altitude above 400ft you feel you would need if you were not feeling on top of your game that day. 
i do have a limitation on my autopilot that i can not add more flaps than take-off setting and i have to sit in the left seat no right seat autopilot flying. Also a limitation no autopilot below 80 kias. That last one is a real eye opener for me as i was on an approach and got down to 75 kias and the autopilot said your aircraft and checked out. I thought there was something wrong with the autopilot until i looked up in the poh and found that speed limitation and i was like well that’s why it quit.