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Rethinking personal minimums

Ed_Wischmeyer

Well Known Member
On the summertime IFR thread, there was a comment about personal minimums. Rather than bury this response at the end of that thread...

If you think about the challenges one incurs on a flight, you don't want too many challenges on the entire flight, and you don't want too many challenges at one time.

So if you're tired, that's a challenge. Turbulence on the entire flight is a challenge. Dodging cumulus buildups for the entire flight is a challenge. An unfamiliar airplane, or being out of currency enough that you're a bit uncomfortable is a challenge. Pressure to get there is a challenge. So this flight might be a good candidate for being cancelled, even if it's VFR. When I had my RV-4, I counted challenges as "gray areas," and cancelled flights if there were too many gray areas.

Now consider an instrument approach but well above minimums. Unfamiliar ATC can be a challenge, as can be a strong, gusty crosswind, and a wet runway. Low visibility but still above minimums can make it a challenge. Trying to figure out alternatives when the published missed approach procedure goes right through a thunderstorm is a challenge. Lots of challenges at once can be reason to avoid that situation.

So the point of personal minimums is not appropriately discussed in the context of just approach minimums -- you should be able to fly any approach to minimums if you have to. A more appropriate set of minimums are: how many total challenges on the flight; and how many challenges might you encounter at once.

This concept was written for the original Eclipse Jet flight safety manual.
 
Also worth considering, is your own condition when they occur. If you expect to be tired, dehydrated, needing to go to the bathroom, or whatever else, that increases the difficulty of the challenge.

I know that after a day's flying in turbulence, at the higher elevations (teens) that I generally fly, that all of the above might apply at once to me.

Dave
 
Thank-you Ed! Good stuff.
Even for us VFR low an? slow folks there are plenty of challenges that deserve more careful consideration than they often get (speaking for a friend) when we don?t fly enough.
Hurry to get airborne, unfamiliar route, airspace, and runway headings vs crosswinds, unexpected headwinds vs fuel, hurry to get on the ground, density altitude, obstacles, changing weather, thick haze and smoke, maintaining focus, keeping head and eyes moving...(others please add).
While I?m in ?thinking safety mode?, I?m going to make a list of these and review it while flight planning and again before each launch.
Thank-you again,
Dave
 
Good stuff.

The one personal limit that applies to all of the variables is fatigue. After making some basic mistakes, and not executing some challenging situations at my best when I was fatigued, I now govern the length of my legs and days better.

Everyone has their own fatigue factor. Flying tired, mentally and/or physicaly, if they can be separated, you simply are not at your best.
 
Checklist

The concepts that are being talked about have been around for a long, long time.

How many remember the IMSAFE checklist?

Illness...
Medication...
Stress...
Alcohol...
Fatigue...
Emotion...
 
They sure have, Bob. Yet we’re still crashing airplanes.
I think any time and any way we can inject safety into our conversations and conscienceness it is a good thing. Never know what little tidbit of info might help someone (especially me!)
 
The concepts that are being talked about have been around for a long, long time.

How many remember the IMSAFE checklist?

Illness...
Medication...
Stress...
Alcohol...
Fatigue...
Emotion...

I've always thought these were out of chronological order.
Rearranging:

Stress
Alcohol
Emotion
Fatigue
Illness
Medication

:eek:
 
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