Full stalls in a multi engine

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Skyknight320

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Skyknight320
When I was doing my multi engine training in an Aztec in the early 1990's, I was taught and the PTS also did not require full power-on stalls, but rather recover at the first indication of a stall. The current ACS now requires full power-on stalls. This seems dangerous, if you had an engine failure occur near red line. For anyone that has done a recent multi check-ride, did the examiner really want to see this done?
 
ACS Task C. Power-On Stalls under Skills:
Acknowledge cues of the impending stall and then recover promptly after a full stall occurs.
 
I read that as 'full stall, power on,' not 'stall, full power on.'

Nauga,
parsley
 
Skyknight320 said:
ACS Task C. Power-On Stalls under Skills:
Acknowledge cues of the impending stall and then recover promptly after a full stall occurs.
Click to expand...
Which ACS?
What are you imagining the ACS requires the approach to the stall to look like, and what would happen if an engine failed near published Vmca?
 
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It is the private pilot ACS https://www.faa.gov/training_testing/testing/acs/media/private_airplane_acs_change_1.pdf
A-14 Addition of an Airplane Multiengine Land Rating to an existing Private Pilot Certificate.
The chart shows if you currently have a ASEL rating then to add the multi, Areas of Operation VII All need to be competed. If you look at Areas of Operation VII Slow Flight and Stalls, Task C. Power-On Stalls:
Skills
Set power to no less than 65 percent power
Acknowledge cues of the impending stall and then recover promptly after a full stall occurs.

Also the task title is "Power-On Stalls"

Since this is the same ACS used for the ASEL, the power-on stall would be the same, nose must break then recover just like you would do the full power on stall in a single. In a twin near Vmca, if one engine failed you could end up in a Vmc roll.

I couldn't find an old PTS from the 1990's but as I recall, full power-on stalls were not required in a twin.
 
MauleSkinner said:
If you don’t have full power, published Vmca is largely irrelevant.
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In a turbo Cessna 310 even at 65% it is a very high pitch attitude and difficult to get the full stall. So I am reading the ACS correctly and full power on stalls need to be demonstrated for a private pilot multiengine add on?
 
Skyknight320 said:
In a turbo Cessna 310 even at 65% it is a very high pitch attitude and difficult to get the full stall. So I am reading the ACS correctly and full power on stalls need to be demonstrated for a private pilot multiengine add on?
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Depends what you mean by “full power on stalls”, but yes.

I’d also suggest reading the appropriate appendices.
 
Many examiners have you use a reduced power so that extreme ATTITUDE isn’t required.
 
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A couple comments, since I've done a lot of multiengine training lately.

1) Effective Vmc is almost always lower than the published value, due to altitude, CG location, etc.

2) Power-on stalls need not be done at full power. The ACS allows for this. At a reduced power setting, effective Vmc is even lower and really shouldn't be an issue.
 
We did power on and power off stalls plus VMC demos. The power on stuff was not full chooch.. maybe 16-18 inches only

If you understand the mechanics and how to react I really don't see this as some super scary thing

Both power levers to idle/nose down, wings level, gently recover pitch.. he also get a fairly wide margin of warning where you feel the rudder start to buffet out in a vmc demo

I would argue these are important concepts to understand and get familiar with so they become second nature

Should you have some power failure in a twin someday and get your attention distracted focusing on the instruments while flying approach it is not impossible that you could enter a vmc critical situation. Being able to instinctively recognize that with the correct actions could save the lives of yourself, your passengers, and people on the ground..
 
Twins with extended prop hubs, like the Aztec and Twin Comanche, to name a couple, have a limitation in the rpm, generally 2200, to avoid over-stressing the crank in a full stall. This limitation is going to factor in, and in some cases, trump the ACS.
 
MauleSkinner said:
Which ACS?
What are you imagining the ACS requires the approach to the stall to look like, and what would happen if an engine failed near published Vmca?
Click to expand...

What if it did
Skyknight320 said:
I meant to say power on full stall
Click to expand...

Who does a full power on stall in about any airplane? 65% power is required for the maneuver.
 
Even in high-performance SINGLES we do power-on stalls at less than full power, to avoid the scary-high pitch angles.
In a twin with two big engines that should be especially true.

- Martin
 
A late friend, told me that when he was instructing in B-29's, stalls in a sixty degree bank were a requirement. Thats a two G bank and all training was done with a full crew.
 
Maxnr said:
A late friend, told me that when he was instructing in B-29's, stalls in a sixty degree bank were a requirement. Thats a two G bank and all training was done with a full crew.
Click to expand...
Things were a lot more entertaining back when only “real men” flew airplanes.
 
Clip4 said:
What if it did


Who does a full power on stall in about any airplane? 65% power is required for the maneuver.
Click to expand...

Just did one in my 310 for my MEI. Key is the set up for the maneuver by slowing to 90kts clean, then introduce power WHILE pitching up with a 20deg bank. You’ll get first indication at about 15 deg of pitch quickly followed by a buffer. Then recover. Very easy.

We also did full stalls power on and power off two engine. The 310 breaks gently almost straight ahead. Beautiful airplane.

Now if you stall in the Vmc demo without the proper corrections, the 310 has been known to have a mean Vmc roll. I don’t plan on finding out.


Sent from my iPhone using Tapatalk
 
Fracpilot said:
Just did one in my 310 for my MEI. Key is the set up for the maneuver by slowing to 90kts clean, then introduce power WHILE pitching up with a 20deg bank. You’ll get first indication at about 15 deg of pitch quickly followed by a buffer. Then recover. Very easy.

We also did full stalls power on and power off two engine. The 310 breaks gently almost straight ahead. Beautiful airplane.
Click to expand...

What power settings MP and RPM did you use for the power on full stall?
 
Skyknight320 said:
What power settings MP and RPM did you use for the power on full stall?
Click to expand...

PM your email. I put together a sheet for my MEI ride that has all of the settings for each maneuver on the 310.


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