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5 minutes ago, midlifeflyer said:

I'm sure that has killed a few people who thought, "it's only a 3000 ft little hill. Nothing to worry about" as a normal mountain downdraft led to a CFIT. 

It gets people flying into Mountain Air, a private air park north of KAVL. At 4432 msl, it's the highest airport east of The River, on the flank of Mt. Mitchell, the highest peak east of The River at 6684 msl.

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Not over weight..... not using all of the available runway... then the mythical 50’ tree off in the distance wasn’t so mythical...
The evidence points to...  an assumption being made... 
There is so much going on with a change of DA...
  • power produced is less...
  • lift generated is less...
  • The AOA needed to produce adequate lift is increased...
  • So the drag encountered is even more...
  • The system gets more sensitive to every extra pound added to the fuel tanks...
  • extra weight or extra AOA also increases the stall speed...
The PIC was coming up on graduation from college with an aviation related degree. The passengers were also school mates...
They had to know better.
Lesson learned... no matter how smart you are... don’t make an assumption about runway length....
Try on a couple of calculations around the edges of the envelope....
  • loaded to MGTW...
  • Set the available runway length. I use 2k’ to make case study things easy to remember...
  • put a mythical tree line out there...
  • increase the temp/DA in 10°F increments...
  • decrease available runway in chunks of 200’...
At what temp does your plane decide... NoGo...?
At what runway length does your plane decide... NoGo...?
 
We can take this idea to the next level... add a level of reality to the system...
(Assume) The POH numbers are pretty good. They are based on reality....  now, to prove that they apply to your plane....
We can actually measure our actual T/O distances using an app and a waas source...  many portable ADSB-in systems have the required waas source... (unfortunately the internal gps of an iPad isn’t accurate enough for this task)... one app that works well is called CloudAhoy...
In the end...
You will find that...
  • DA matters...
  • Even in Flatistan...
  • It counts even more, the closer to MGTW you get...
  • It counts even more, the hotter the OAT is...
The data starts to fall apart rapidly nearing the edges of the envelope... that is the big reason why we have limits to what MGTW actually is...
To make this an easy to do exercise... The POH drag your finger calculation has been simplified by somebody around here to show that it can be done....
I would like to see Mooney/MAPA bless the app approach of calculating T/O distances... it is too easy to make a fat fingered mistake using the paper charts... or slip doing the math from a chart...
This would be a great method to improve upon the know before you go idea...
Good decisions start with good data... 
PatrickF (a different Patrick) recently had posted his T/O distance calculations that he digitized from the Mooney graphs for his Long Body...  looks like a really viable way to make easy DA related Go/NoGo decisions...
PP thoughts only, not a CFI...
Best regards,
-a-

Although you can argue not using all available runway may have made the difference, I don’t think so. The combination of departing in the dark and allowing the plane to drift off left of centerline into the trees is my recollection of what happened. If the plane maintained centerline it would have been fine but he lacked the visual cues in the dark to help track straight where it was mostly clear. Even less right rudder would have brought the plane down sooner even with more runway.
ADM (night not being able to see obstacles off to the sides, not using all runway) and basic airmanship (not tracking centerline and never letting the plane accelerate to Vy, maybe not even to Vx given stall horn was intermittently going off the whole departure sequence)

I know most blame it on not using all runway, but I thought that wasn’t the big factor most made it out to be - just my option.


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6 hours ago, KLRDMD said:

Mountains are not mountains. My field elevation is 3,000 feet and in the summer density altitude gets well above twice that. People in the west based around real mountains may have a field elevation of 7,000 ft. Peaks in the west get near 15,000 ft. A 3,000 ft "mountain" is not the same. 

So true - our field elevation is just a few feet shy of 7000' and the big mountain a few miles to the northwest is 12,633'... so it's important to know what's nearby.  By the way, there's a B24 crash site on the side of the mountain and every year a US flag's flying from the landing gear strut...  it's a hike worth doing, if you're in the area.  The hike's not a marked trail,  but you can find directions with some Google fu.

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6 hours ago, kortopates said:


Although you can argue not using all available runway may have made the difference, I don’t think so. The combination of departing in the dark and allowing the plane to drift off left of centerline into the trees is my recollection of what happened. If the plane maintained centerline it would have been fine but he lacked the visual cues in the dark to help track straight where it was mostly clear. Even less right rudder would have brought the plane down sooner even with more runway.
ADM (night not being able to see obstacles off to the sides, not using all runway) and basic airmanship (not tracking centerline and never letting the plane accelerate to Vy, maybe not even to Vx given stall horn was intermittently going off the whole departure sequence)

I know most blame it on not using all runway, but I thought that wasn’t the big factor most made it out to be - just my option.


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Paul,

We are in agreement, but, I wasn’t clear enough...

1) There was a few things going wrong on the T/O run and departure....

2) DA and the short runway is where I am putting the focus, for my discussion part of this thread.

3) Had Patrick, known the DA, and calculated a Take Off distance, And decided to depart... He was PIC and qualified to do these steps...

4) I would expect that he would have gladly used the entire runway...  He didn’t mind doing extra work to get the job done right.  He went all the way to CA for a nice paint job... the full four year college degree... not a more direct route...  and... he was making phone calls one day... inviting a bunch of people he never met before, to an NJMP fly-in we had never organized before...

5) He was more than educated in the arts and sciences of aviation... and fully capable of the math involved...

6) Something didn’t click, enough, that day...to say... “gent’s, I think I’ll back taxi the whole way...”

7) I lost a new friend that day...

8) Knowing my beginning in aviation, I had the skill to do the math... But thought ‘real’ pilots didn’t use that ancient POH stuff... they somehow had actual experience memorized or something....

9) With a couple of decades of flying under my belt... a couple of engineering degrees... additional experience in machine design, machine construction, and serialization.... my memory isn’t THAT good. It never was, and in the future, it won’t be that reliable...  but, the good news.... we have a solid logical solution....

10) We can...

  • Reliably calculate our machine’s performance...
  • Use technology to tell us that our machine is (or isn’t) still meeting the expectations of the family of machines, in our serial number range.
  • Use our performance calculations to predict the next set of T/O lengths....

We are still going to rely on our training to determine other aspects of the go/No Go decision, especially the safety factor to use with this data...  leaving room for how we perform the T/O procedure... some of us don’t use max performance procedures all the time...

 

I certainly appreciate Paul’s coaching on the rest of the T/O procedure... knowing where the best place to be when Plan A has gone awry...

 

So... I think I may have posthumously promised Patrick, in his memory, to discuss the one thing that I think could have made A difference...

 

  • It made a difference in the method I use to calculate T/O distances...
  • It made a difference in my willingness to use the whole runway...  except where everyone at Mooney Summit was departing in front of me and not using all 7k’ (?) or so... 6k’ seemed to be enough that day...  :)
  • It made a difference when I selected the 310hp option when performing a needed engine OH.  For a few amu more....
  • It makes a difference each time I get a DA report delivered to my phone....

 

My promise was to discuss DA and its effect on machine performance...  enough to get...

  • A newer pilot to look further into the topic 
  • A current pilot to update his thinking or his method of supporting his DA related decisions...
  • A highly experienced pilot to share his knowledge on the subject...
  • All Mooney Pilots discuss this topic openly, knowingly, intelligently....

 

Some of the nicest places in the Mooney world have shorter runways, or they are in higher places...

Thanks to Dr. K. for this thread... a great reminder for the issues we face in the warmer seasons ahead...

 

Then same discussion at the end of all my posts... I am a Private Pilot, only... Not a CFI.

 

One of my favorite topics... simply the discussion that gets people to open up on how they handle performance details...

Best regards,

-a-

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12 hours ago, Hank said:

It gets people flying into Mountain Air, a private air park north of KAVL. At 4432 msl, it's the highest airport east of The River, on the flank of Mt. Mitchell, the highest peak east of The River at 6684 msl.

Yep. Know the place. I flew in a few years ago when I moved to NC (sorry, not a Mooney).

 

 

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11 hours ago, carusoam said:

 

Paul,

We are in agreement, but, I wasn’t clear enough...

1) There was a few things going wrong on the T/O run and departure....

2) DA and the short runway is where I am putting the focus, for my discussion part of this thread.

3) Had Patrick, known the DA, and calculated a Take Off distance, And decided to depart... He was PIC and qualified to do these steps...

4) I would expect that he would have gladly used the entire runway...  He didn’t mind doing extra work to get the job done right.  He went all the way to CA for a nice paint job... the full four year college degree... not a more direct route...  and... he was making phone calls one day... inviting a bunch of people he never met before, to an NJMP fly-in we had never organized before...

5) He was more than educated in the arts and sciences of aviation... and fully capable of the math involved...

6) Something didn’t click, enough, that day...to say... “gent’s, I think I’ll back taxi the whole way...”

7) I lost a new friend that day...

8) Knowing my beginning in aviation, I had the skill to do the math... But thought ‘real’ pilots didn’t use that ancient POH stuff... they somehow had actual experience memorized or something....

9) With a couple of decades of flying under my belt... a couple of engineering degrees... additional experience in machine design, machine construction, and serialization.... my memory isn’t THAT good. It never was, and in the future, it won’t be that reliable...  but, the good news.... we have a solid logical solution....

10) We can...

  • Reliably calculate our machine’s performance...
  • Use technology to tell us that our machine is (or isn’t) still meeting the expectations of the family of machines, in our serial number range.
  • Use our performance calculations to predict the next set of T/O lengths....

We are still going to rely on our training to determine other aspects of the go/No Go decision, especially the safety factor to use with this data...  leaving room for how we perform the T/O procedure... some of us don’t use max performance procedures all the time...

 

I certainly appreciate Paul’s coaching on the rest of the T/O procedure... knowing where the best place to be when Plan A has gone awry...

 

So... I think I may have posthumously promised Patrick, in his memory, to discuss the one thing that I think could have made A difference...

 

  • It made a difference in the method I use to calculate T/O distances...
  • It made a difference in my willingness to use the whole runway...  except where everyone at Mooney Summit was departing in front of me and not using all 7k’ (?) or so... 6k’ seemed to be enough that day...  :)
  • It made a difference when I selected the 310hp option when performing a needed engine OH.  For a few amu more....
  • It makes a difference each time I get a DA report delivered to my phone....

 

My promise was to discuss DA and its effect on machine performance...  enough to get...

  • A newer pilot to look further into the topic 
  • A current pilot to update his thinking or his method of supporting his DA related decisions...
  • A highly experienced pilot to share his knowledge on the subject...
  • All Mooney Pilots discuss this topic openly, knowingly, intelligently....

 

Some of the nicest places in the Mooney world have shorter runways, or they are in higher places...

Thanks to Dr. K. for this thread... a great reminder for the issues we face in the warmer seasons ahead...

 

Then same discussion at the end of all my posts... I am a Private Pilot, only... Not a CFI.

 

One of my favorite topics... simply the discussion that gets people to open up on how they handle performance details...

Best regards,

-a-

Well said Anthony!

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12 hours ago, carusoam said:

 

 

My promise was to discuss DA and its effect on machine performance...  enough to get...

  • A newer pilot to look further into the topic 
  • A current pilot to update his thinking or his method of supporting his DA related decisions...
  • A highly experienced pilot to share his knowledge on the subject...
  • All Mooney Pilots discuss this topic openly, knowingly, intelligently....

 

 

Best regards,

-a-

You've definitely succeeded with me. I've understood and been aware of DA since being a student (before my PPL, I'm still a student of the art). But some of the points you brought up earlier about finding out what MY plane will do under different sets of circumstances has made me decide to do a series of tests to know for sure. Thanks for your contributions to this forum.

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On 4/19/2019 at 3:29 PM, KLRDMD said:

Mountains are not mountains. My field elevation is 3,000 feet and in the summer density altitude gets well above twice that. People in the west based around real mountains may have a field elevation of 7,000 ft. Peaks in the west get near 15,000 ft. A 3,000 ft "mountain" is not the same. 

The valley in WV I described spends most of its time shrouded in mist and fog.  There are no instrument approaches, by the way.   Most of the mountains in the East and the South spend most of their time in weather.  They don't call them the Smokey Mountains because of fires.  I can only dependably get past them in high summer and early fall, and even then its problematic.

The Western mountains don't have weather on that scale.  And places where density altitudes get that high often have long runways.

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I've always loved the mountains. The Smokey's were my first love as I went to high school in Asheville. Now having just moved to Denver, I'm loving the big mountains! I won't have the Mooney there until June, but looking forward to exploring all the little airports in and around the Rockies.

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