M20F crash Carrizozo NM 8/2/24

[Shadrach]

27 minutes ago, DCarlton said:

I'll have to pay more attention and write it down but I think I'm seeing highs in the 1390s.  Not sure if that's at sea level though.  Interestingly I'm hoping to get from SOCAL to ELP through NM in a week or so; monsoon season permitting.  

I doubt that. An 8.7:1 Lycoming won’t generate a peak EGT reading much above  1500°. If you we”re seeing 1390° at full rich than you’d likely be less than 150° ROP

[DCarlton]

1 minute ago, Shadrach said:

I doubt that. An 8.7:1 Lycoming won’t generate a peak EGT reading much above  1500°. If you we”re seeing 1390° at full rich than you’d likely be less than 150° ROP

Will take a closer look.  Need to download my engine monitor too; never been through that exercise.  

[201Mooniac]

43 minutes ago, DCarlton said:

I'll have to pay more attention and write it down but I think I'm seeing highs in the 1390s.  Not sure if that's at sea level though.  Interestingly I'm hoping to get from SOCAL to ELP through NM in a week or so; monsoon season permitting.  

I use 1380 on mine and that seems to work well for me but I've seen a lot of variability between aircraft for EGT values that I think are associated with installation differences so it is best to figure out the number that works for your aircraft installation.

[201Mooniac]

12 minutes ago, Shadrach said:

I doubt that. An 8.7:1 Lycoming won’t generate a peak EGT reading much above  1500°. If you we”re seeing 1390° at full rich than you’d likely be less than 150° ROP

I can see a peak EGT of over 1530 in my install.  I typically see 1370-1380 as full rich at sea level.

[Ragsf15e]

I think there’s some dependence on probe position.

You guys potentially have ff too low at takeoff too… what is your sea level fuel flow?

Edited August 10, 2024 by Ragsf15e

[Shadrach]

44 minutes ago, 201Mooniac said:

I can see a peak EGT of over 1530 in my install.  I typically see 1370-1380 as full rich at sea level.

Like I said, “much above”…  1530° is top of the range. If that cylinder is 1370°-1380° at full rich, than it is only 150°-160° ROP at SL and full rich.  That is suboptimal and I am surprised you’re not encountering elevated CHTS.

[Ragsf15e]

Just now, Shadrach said:

Like I said, “much above”…  1530° is top of the range. If that cylinder is 1370°-1380° than it is only 150°-160° ROP at SL and full rich.  That is suboptimal and I am surprised you’re not encountering elevated CHTS.

Ha! You’re back!  And you just barely beat me to it!

[Shadrach]

8 minutes ago, Ragsf15e said:

Ha! You’re back!  And you just barely beat me to it!

My peak EGTs vary quite a bit from cylinder to cylinder. 3 will break into the low 1500s, 2 tops out around 1470°. I don’t lean on 1 and 4 so I don’t remember where they peak. Full rich everything is low 1200s (used to be high 1100s but my servo is middle aged).  All my cylinder are a minimum of 230° ROP when full rich at sea level. I wish they were a little richer. While probe certainly affects max raw temp. The number of degrees from peak to full rich should be accurate.

[201Mooniac]

1 hour ago, Shadrach said:

Like I said, “much above”…  1530° is top of the range. If that cylinder is 1370°-1380° at full rich, than it is only 150°-160° ROP at SL and full rich.  That is suboptimal and I am surprised you’re not encountering elevated CHTS.

I'll ask my MSC to look at it but I haven't had issues with high CHTs except occasionally when the temps are at or above 95F and then they still rarely exceed 385.  I'm curious, what do you expect to see for sea level FF when full rich?

[Shadrach]

12 minutes ago, 201Mooniac said:

I'll ask my MSC to look at it but I haven't had issues with high CHTs except occasionally when the temps are at or above 95F and then they still rarely exceed 385.  I'm curious, what do you expect to see for sea level FF when full rich?

On a standardish day? Around 18gph.

[201Mooniac]

9 minutes ago, Shadrach said:

On a standardish day? Around 18gph.

Interesting, I usually see betweem 16.8 amd 17.2 gph.  I guess maybe I'm running a little too lean.  Thanks, this is helpful to know.

[ottorecker]

We landed in Carrizozo about a month ago.  Lets just be kind and say the runway needed a "trim".  There was a good amount of up to 3+ feet tall grass tufts growing randomly through the cracks of the asphalt along most of the runway.  Was it like that a week ago? I don't know, but my guess is it's probably likely.  Bill, the airport manager and great guy was having some health issues and, if I had to speculate, wasn't aware of the the tall grass on the runway (his health issue is pertinent in this case but I'm going to give him HIPPA and not divulge it here).  I'm not saying some scruffy grass caused the crash but It certainly would have been a distraction departing F37.  It was for me a month ago.

That area (and much of New Mexico) is susceptible to powerful dust devils which may or may not distinctly visible.  There were at least two that were distinctly visible close to the airport the day we departed.  Could there have been more stealthy ones?  Perhaps.  It's likely pilots would recognize a majority of them, but if they were concerned about the tall grass on the runway might they have not?  I've been in and out of that airport a handful of times.  It's not a particularly challenging airport for takeoffs even on hot days with proper procedures but an added anomaly could escalate a takeoff threat.

Our New Mexico dust devils can be formidable.  If there was one on or near the departure end of the runway that would likely have a considerable impact on aircraft performance.

I'm just speculating here but if you are not familiar at flying in the arid west in the summertime realize that those mini-tornados can be a threat.  I'm very glad the occupants are fine.  Hopefully they are on MS and can give us a first person account.

Watch out for those dust devils on departure (and arrival).

[Ragsf15e]

8 minutes ago, Shadrach said:

On a standardish day? Around 18gph.

Seems about right.  Mine shows 18.5ish.

[Shadrach]

1 hour ago, 201Mooniac said:

Interesting, I usually see betweem 16.8 amd 17.2 gph.  I guess maybe I'm running a little too lean.  Thanks, this is helpful to know.

I just check my POH and it says 18.6 on a standard day. So @Ragsf15e is about  dead on.

[GeeBee]

9 hours ago, ottorecker said:

We landed in Carrizozo about a month ago.  Lets just be kind and say the runway needed a "trim".  There was a good amount of up to 3+ feet tall grass tufts growing randomly through the cracks of the asphalt along most of the runway.  Was it like that a week ago? I don't know, but my guess is it's probably likely.  Bill, the airport manager and great guy was having some health issues and, if I had to speculate, wasn't aware of the the tall grass on the runway (his health issue is pertinent in this case but I'm going to give him HIPPA and not divulge it here).  I'm not saying some scruffy grass caused the crash but It certainly would have been a distraction departing F37.  It was for me a month ago.

That area (and much of New Mexico) is susceptible to powerful dust devils which may or may not distinctly visible.  There were at least two that were distinctly visible close to the airport the day we departed.  Could there have been more stealthy ones?  Perhaps.  It's likely pilots would recognize a majority of them, but if they were concerned about the tall grass on the runway might they have not?  I've been in and out of that airport a handful of times.  It's not a particularly challenging airport for takeoffs even on hot days with proper procedures but an added anomaly could escalate a takeoff threat.

Our New Mexico dust devils can be formidable.  If there was one on or near the departure end of the runway that would likely have a considerable impact on aircraft performance.

I'm just speculating here but if you are not familiar at flying in the arid west in the summertime realize that those mini-tornados can be a threat.  I'm very glad the occupants are fine.  Hopefully they are on MS and can give us a first person account.

Watch out for those dust devils on departure (and arrival).

 

[N201MKTurbo]

Dust devils are not rare around here. There are some days when flying around here you can scan the desert and see them all over the place.

Back when I was commuting to Tucson, I avoided them all the time. The late afternoon when I was returning home was when they were the most prevalent. I always wondered what it would be like to fly through one? So one day there was a good size one right in my flight path about 6 miles south of the airport. It was about 100 feet in diameter. I flew right through the center of it at about 1000 AGL. Been there done that got the T shirt, don’t need to go back. 
 

They are easy to fly around. If you miss them by a few feet it is ok and you won’t feel a thing, but they are surprisingly powerful right in the middle. Kind of like hitting a speed bump at freeway speeds.

[Shadrach]

2 hours ago, N201MKTurbo said:

Dust devils are not rare around here. There are some days when flying around here you can scan the desert and see them all over the place.

Back when I was commuting to Tucson, I avoided them all the time. The late afternoon when I was returning home was when they were the most prevalent. I always wondered what it would be like to fly through one? So one day there was a good size one right in my flight path about 6 miles south of the airport. It was about 100 feet in diameter. I flew right through the center of it at about 1000 AGL. Been there done that got the T shirt, don’t need to go back. 
 

They are easy to fly around. If you miss them by a few feet it is ok and you won’t feel a thing, but they are surprisingly powerful right in the middle. Kind of like hitting a speed bump at freeway speeds.

I was hit by a Dust devil in Utah while driving a UHaul. When it was over, I was one lane over from where I started and greatful to still be on pavement. Can only imagine how bad it would be in an airplane at low altitude.

[A64Pilot]

We used to talk about them when sitting in the desert in South West Asia, the topic usually was what would happen to a parachutist if he got into one.

Our best guess was that maybe the chute would get twisted up and then he’d drop like a rock, or would he spin with the chute?

I hate the Damn things, there is little noise associated with them, one day we were all in the tent supposedly sleeping, I say supposedly because you can’t sleep in 120 degrees laying in a pool of sweat. The sides of the tent stayed rolled up due to the heat of course, anyway suddenly the world exploded, everything in the tent got thrown around and covered in dirt.

We were hit by one of the things, Shamals sucked too but they didn’t sneak up on you, the dirt tornadoes do.

Edited September 30, 2024 by A64Pilot