Yeppers! I'm that jerk.digits_ wrote:So YOU are the one that makes all those labels fade
The replacement stickers for mine are fairly inexpensive so...Runaway Trim
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Broken Slinky
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Re: Runaway Trim
The replacement stickers for mine are fairly inexpensive so...
Re: Runaway Trim
Runaway trim is a mildly interesting one in the Citation 500 series. Basically the checklist says:
1. hold down the red button on the control column to disable the trim (the button is on the left side of the control yoke, so it's natural to use your left hand to do this)
2. Pull the electric trim circuit breaker and then manually retrim and land as soon as practical etc etc
The thing is, the circuit breaker is on the left side panel next to the Captain's left knee, so if you're in the left seat and the Pilot Flying, the checklist would have you literally crossing your right arm under your left to pull the circuit breaker while fighting runway trim with your left arm. If your luck is bad enough to experience this, I bet it's gonna end up being IFR at night, so imagine that particular workload right after takeoff for example.
Unfortunately, we don't have to imagine it. It may have happened to a Cessna 500 series departing Cleveland Lakefront airport. TLDR: They depart, shortly afterwards report runaway trim and shortly after that, impact the surface of Lake Erie.
https://www.ntsb.gov/safety/safety-recs ... 13_128.pdf
They can't positively identify it 100% as runaway trim but it was either that or inadvertant autopilot selection and I find it hard to believe neither of them thought to click on the autopilot disconnect button (which is actually the same red button we hold down while reacting to a runaway trim event). From the CVR it appears they were fighting it all the way down and the autopilot on the 550 doesn't require that much force to disengage, like it's easily doable for an average adult.
Anyway;
In our operation we mostly fly as Co-Captains, so we swap seats on a regular basis, but it's always the pilot in the left seat who is the Pilot Flying. I want to be proactive, so we add a step in our training. First thing we do is hand control over to the right seat pilot who holds down his/her red button and retrims manually while the left seat pilot pulls the cb. I'm honestly surprised it's not in the checklist but it's the safe thing to do so that's what we brief and that's what we do.
1. hold down the red button on the control column to disable the trim (the button is on the left side of the control yoke, so it's natural to use your left hand to do this)
2. Pull the electric trim circuit breaker and then manually retrim and land as soon as practical etc etc
The thing is, the circuit breaker is on the left side panel next to the Captain's left knee, so if you're in the left seat and the Pilot Flying, the checklist would have you literally crossing your right arm under your left to pull the circuit breaker while fighting runway trim with your left arm. If your luck is bad enough to experience this, I bet it's gonna end up being IFR at night, so imagine that particular workload right after takeoff for example.
Unfortunately, we don't have to imagine it. It may have happened to a Cessna 500 series departing Cleveland Lakefront airport. TLDR: They depart, shortly afterwards report runaway trim and shortly after that, impact the surface of Lake Erie.
https://www.ntsb.gov/safety/safety-recs ... 13_128.pdf
They can't positively identify it 100% as runaway trim but it was either that or inadvertant autopilot selection and I find it hard to believe neither of them thought to click on the autopilot disconnect button (which is actually the same red button we hold down while reacting to a runaway trim event). From the CVR it appears they were fighting it all the way down and the autopilot on the 550 doesn't require that much force to disengage, like it's easily doable for an average adult.
Anyway;
In our operation we mostly fly as Co-Captains, so we swap seats on a regular basis, but it's always the pilot in the left seat who is the Pilot Flying. I want to be proactive, so we add a step in our training. First thing we do is hand control over to the right seat pilot who holds down his/her red button and retrims manually while the left seat pilot pulls the cb. I'm honestly surprised it's not in the checklist but it's the safe thing to do so that's what we brief and that's what we do.
Re: Runaway Trim
Doesn't that create unnecessary confusion as well? Handing over an untrimmed airplane? No matter how well you prepare, the PNF will never be able to accurately anticipate how much force will be required initially. He might not even know if it is nose down or nose up runaway.Sulako wrote:First thing we do is hand control over to the right seat pilot who holds down his/her red button and retrims manually while the left seat pilot pulls the cb. I'm honestly surprised it's not in the checklist but it's the safe thing to do so that's what we brief and that's what we do.
As an AvCanada discussion grows longer:
-the probability of 'entitlement' being mentioned, approaches 1
-one will be accused of using bad airmanship
-the probability of 'entitlement' being mentioned, approaches 1
-one will be accused of using bad airmanship
