Windy & Challenging Short Field Takeoff

[kath]

Just to be clear...
A) "If you are wondering whether the operation is safe, don't do it." <--- Agree for the most part (not *literally*, since I "wonder" about safety all the time... but I understand the mental approach you're describing here)
B) "If you have to run a performance calculation to decide whether something is safe, don't do it." <--- Disagree strongly.
These are two very different statements.

I found FlyingMonkey's calculations in the video really refreshing to see. "Yeah, I should be doing that more often," I told myself. "It should be more part of the culture..."
That being said, I would've taken off into the wind and just turned away from the terrain.

 

[Sinistar]

Obviously several have said take off into the wind and turn for terrain.

@FlyingMonkey, you did all the math to determine the climb rate for the upwind takeoff obstacle directly in front. That was pretty cool. But (from the video) its like you didn't give the takeoff with slow turn right any thought. But I am guessing you did? Does the video not show the terrain to the right in a way that you saw it...so maybe we're not seeing what you did.

When watching it again to see if you mentioned taking off into the wind and turning I noticed you said something like "Lets let the oil temperature come up to speed." I could tell you were getting kind nervous right there.

 

[mr_happyland]

Fun video as usual Eric. I've flown into Agua Caliente in my Tiger and encountered a very similar situation. In my case, upon arrival winds were favoring rwy 11, so I had to make that awkward approach next to the mountain. First attempt was a go-around. The second was "fun" but worked out fine. After a couple hours at the hot springs, the winds shifted and, similar to you, was showing 10-15 kts favoring 29...towards the mountain. It was also hot so DA played a factor. Tiger isn't exactly a short field airplane, but it was just myself. After running the numbers, I opted for 29, into the wind towards the mountain. In my situation, I wouldn't have attempted a downwind takeoff, given my calculations at the time. Obviously your plane has different performance numbers. While the view is a little intimidating, takeoff was pretty much a non event. With the headwind, I was up in the air well before the windsock in the middle and a gradual right turn was all it took to avoid the terrain.

 

[idahoflier]

Not trying to pile on and maybe it has already come up and I missed it, but one other consideration is you had less than 4 seconds from unsticking to reaching the end of the runway (which your calculations and video confirmed so kudos on being accurate). Doing that in a single engine aircraft is just too risky in my mind. One other consideration is in an abort/overrun scenario would you rather be going through the desert scrub at 62 kts or 102 kts?

Just my opinion, take it for what it's worth. Looking forward to more family flying videos, I wish my family enjoyed it as much as yours. Blue skies!

 

[smv]

The takeoff numbers were based on guesses at the wind and “rules of thumb.” Where in that POH does it even tell you how to adjust the takeoff numbers for downwind takeoff?

No idea about the OP's POH, but several of the POHs I have include allowances in the Takeoff Data tables (typically as a note, but sometimes as part of the chart) for tailwind takeoff calculations.

 

[kgruber]

Never for 20 knots. 10 sometimes

 

[benyflyguy]

The Bonanza takeoff through the trees was at Mears Field (3W5), Concrete WA. Elevation 267 ft. It is NEVER hot there.

The problem there is that Beech no longer publishes a short field takeoff procedure, and canceled ALL the old SFTPs from ALL manuals. We had to remove the short field procedure from our 67' King Air 65-A90. We didn't and kept it.

If the pilot would have selected approach flaps, he would have been hundreds of feet in the air at the end of the runway.

Happen to have a link for that vid. Was looking on yT but can’t seem to find that one

 

[Sluggo63]

I wouldn't tell anyone NOT to do calculations and ensure the safety of the flight by checking the numbers in their POH.

So if you check the numbers in the POH and they say you're good to go, are you good to go? If not, why check the book?

If you're trying to take off from a 3,000' runway and the book says you need 2,500' will you go? How about 2,750? 2,900? 3,000? Where do you draw the line.

It seems like every year there's a thread started by a newly rated Instrument pilot talking about "personal IFR mins." And half of the crowd pipes in with "YOU SHOULD BE ABLE TO FLY TO THE MINS ON THE PLATE!" But that's what we're talking about here, right? You should be able to use the book numbers. I have no problem with a new IFR pilot giving themselves "personal minimums" until they feel more comfortable. We did it in the Air Force, and we do it (well, the FAA does it) at work.

In the same vein, I also have no problem with someone having "personal takeoff distance" minimums. If you say that you want a 15% pad on your takeoff distance, then so be it. Use it. If your takeoff roll comes out to 2,600' in the example above, then you're good. If it comes out to 2,700'... come up with another plan. Just have something. Run the numbers and stick to your mins.

All I am saying is if you are in doubt of the operation, just don't do it.

That's absolutely good advise, but how do you know when to have doubt? Is it just a feeling? Do we just TLAR everything?

If I really NEED to check whether my airplane can do what I want, I really need to take a step back and question what I'm doing. Do I really NEED to go there. Is there somewhere else that's better suited to my aircraft?

Can't we use that same line of reasoning about anything we do? If I really NEED to check the weather, should I take a step back and question what I'm doing?

 

[FlyingMonkey]

So if you check the numbers in the POH and they say you're good to go, are you good to go? If not, why check the book?

If you're trying to take off from a 3,000' runway and the book says you need 2,500' will you go? How about 2,750? 2,900? 3,000? Where do you draw the line.

It seems like every year there's a thread started by a newly rated Instrument pilot talking about "personal IFR mins." And half of the crowd pipes in with "YOU SHOULD BE ABLE TO FLY TO THE MINS ON THE PLATE!" But that's what we're talking about here, right? You should be able to use the book numbers. I have no problem with a new IFR pilot giving themselves "personal minimums" until they feel more comfortable. We did it in the Air Force, and we do it (well, the FAA does it) at work.

In the same vein, I also have no problem with someone having "personal takeoff distance" minimums. If you say that you want a 15% pad on your takeoff distance, then so be it. Use it. If your takeoff roll comes out to 2,600' in the example above, then you're good. If it comes out to 2,700'... come up with another plan. Just have something. Run the numbers and stick to your mins.

That's absolutely good advise, but how do you know when to have doubt? Is it just a feeling? Do we just TLAR everything?


Can't we use that same line of reasoning about anything we do? If I really NEED to check the weather, should I take a step back and question what I'm doing?

My rule is to use max gross for all performance calculations even when I am way under, apply rules of thumb for tailwind, surface, gradient, and round up on all winds and calculations...and then add 30%. I did that in this case and was right about at the length of the runway with that calculation, which is why I say this was "pushing my personal comfort level." Because the wind was less than what I used in the calculation and we were way under max gross by 400-500 pounds there was a little extra margin built in beyond my default 30%. For clearing obstacles I add 50% to whatever the MGW calculation says.

 

[steingar]

So if you check the numbers in the POH and they say you're good to go, are you good to go? If not, why check the book?

I don't know about you, but my book was written long ago and doesn't account for every contingency. Can you calculate the density altitude? Certain about that? The calculation includes humidity. My book only lists a few. What's the wind, how bad are the gusts? What's the runway surface, and how occluded is it? My book numbers are for a 50 foot obstacle, trees hereabouts plum forgot to stop growing when they hit that height. Moreover, the book numbers are for a brand new airplane from yesteryear being flown by a crack test pilot with chiseled good looks, bags of experience and a girl in every airport. Me, I've got an old airplane being flown by a fat old bald ham-fisted pilot with one cranky old lady. So how certain should I be with those numbers?

This is an easy one. If the little voice in the back of my head says I shouldn't do it I don't. Oh yeah, if I had to rescue my loved ones from the Zombie Apocalypse I might push it some, but usually I see no need. Usually there's another airport where I'm going, or worst case I can find somewhere else to be.

 

[TrueCourse]

Happen to have a link for that vid. Was looking on yT but can’t seem to find that one

https://www.flyaoamedia.com/aviation/my-scariest-moment-as-a-pilot/

That flight was 2010 and was covered in the page above and again by FlightChops.

 

[Sluggo63]

I don't know about you, but my book was written long ago and doesn't account for every contingency. Can you calculate the density altitude? Certain about that? The calculation includes humidity. My book only lists a few. What's the wind, how bad are the gusts? What's the runway surface, and how occluded is it? My book numbers are for a 50 foot obstacle, trees hereabouts plum forgot to stop growing when they hit that height. Moreover, the book numbers are for a brand new airplane from yesteryear being flown by a crack test pilot with chiseled good looks, bags of experience and a girl in every airport. Me, I've got an old airplane being flown by a fat old bald ham-fisted pilot with one cranky old lady. So how certain should I be with those numbers?

So what do you do?

Lets say you and the wife take a trip somewhere to some runway that's shorter than you're used to and you're getting ready to leave and its hotter than you expected, the winds are gustier than you thought and the ramp filled the fuel to the top instead of the tabs like you asked them to. Do you just wing it? Do you just not go?

I kinda get what you're saying. I don't want to sound like a hypocrite. If I'm taking off from my home airport and it's just me and my son I have a pretty good idea that I'll get off the ground, and I won't be running through the charts for that.

Maybe it's your wording that I have a problem with.

If you really have to do the calculations to convince yourself it’s safe you probably shouldn’t do it.

You don't do calculations to "convince" yourself of anything. You do the calculations to ensure that you are capable of doing what you're planning on doing. Then you evaluate the numbers and see if you are comfortable with what they give you. If they are... have a safe flight. If they're not, come up with another plan.

If it isn't blatantly obvious that you can safely do the operation and you need to do calculations to "check" and make certain you can do things, you probably shouldn't do it.

Again, what's "blatantly obvious?" You asked:

Can you calculate the density altitude?

Yes

Certain about that?

More certain about that than just thinking "it's blatantly obvious that it's okay." But I'll take my density altitude calculation and enter it into my performance charts.

What's the wind, how bad are the gusts?

I don't know. How do you determine what the wind is? Is it obvious to you? I'll take my best guess and enter that into my chart too.

What's the runway surface, and how occluded is it?

I'm not sure. But I'll take my best educated guess and add any performance decrements to my performance numbers.

...and so on.

In the end, I will have taken my calculated density altitude and my calculated gross weight and wind component and runway grade and run through a chart and come up with a number that I can look at and see what my airplane should be capable of. I will want a margin of safety but I'll have the confidence that my airplane should come close to what I have. I think that way is better than trying to convince myself that I can just eye ball things and think "it's blatantly obvious to me that this will all work out."

 

[MauleSkinner]

Just to be clear...
B) "If you have to run a performance calculation to decide whether something is safe, don't do it." <--- Disagree strongly.

Likewise. IMO, pilots should
a. Have a really good idea what book performance is for their operations and
b. Have a really good idea how their technique with the airplane compares to book.

I’ve flown with way too many pilots who say, “I never go unless I have at least a 50% safety factor, and then proceed to use almost double their safety factor in a takeoff.

I found FlyingMonkey's calculations in the video really refreshing to see. "Yeah, I should be doing that more often," I told myself. "It should be more part of the culture..."
That being said, I would've taken off into the wind and just turned away from the terrain.

I didn’t watch the video, but it sounds like he used some rules of thumb and came out pretty close. Most rules of thumb are pretty well based in reality, and when properly applied are quite accurate.