Which single line checklist items, when missed, could lead to a crash?

[Hang 4]

Did you even read about what happened?

Yes, I read the entire article. The pilot announced an emergency landing to an runway that did not exist. Then stalled and spun in. No ASI in most GA planes, including an SR22 should not be that much of an emergency. Just fly the freaking plane. Do a lap in the pattern and land. Declare if the pattern is busy and you want to get down. Helmet fire was the cause, pitot cover caused the helmet fire, didn't cause the stall spin.

Yes the pitot cover contributed to it and you should make sure to take it off. What if a bug impales itself in the port on take off? Part of slow flight training is recognizing an incipient stall.

 

[EdFred]

It could kill you, and become a factor absolutely. Like losing an engine mid flight or on takeoff.

No. Losing an instrument is NOT the same as losing an engine. There isn't a damn instrument failure in the plane that will cause a crash. The only thing that contributed to that accident is "Cirrus Pilot."

Like the one on the radio I heard that wanted to declare an emergency in VFR because his nav screen was acting up. Dude, you're in Michigan near the straights. If you can't make it to Harbor Springs by pilotage, you shouldn't be in the air.

 

[MountainDude]

One more I can think of is forgetting (or not knowing) to lean the mixture at high altitude airports.

 

[EdFred]

One more I can think of is forgetting (or not knowing) to lean the mixture at high altitude airports.

I never take off full rich - even at sea level. I always lean for best power. Unless DA is minus 3000, I'm always leaned somewhat. Full engine monitor so, I'm not cooking anything.

 

[Pinecone]

Trim set for landing is unlikely to cause a crash - In many planes it's very close to the takeoff setting, in others you're never going to break ground with that trim setting.

VERY aircraft dependent. In my Mooney, I typically land with full nose up trim. That would make for a VERY EXCITING take off.

I do agree that GA checklists could be better. I have MiraCheck (now Goose Copilot). When I input my checklists, I reordered things to a more logical order for me.

I use GUMPS as a roll out on final last confirmation of important things, and as I roll out for take off, I sweep the power levers, trim and flap settings.

 

[wanttaja]

That is just bad piloting.

I've made two take offs with blocked pitot. One was the old Cessna hinged style that didn't open on t/o roll.

Flew a Citabria for most of my student hours. One day, I was on final. The airspeed started to decrease. I added forward pressure. The airspeed STILL went down. I pushed the nose down as much as I dared, and watched the needle continue to drop. Thought I was going to die.

The needle dropped to zero. Then went past as I shot over the threshold, ~50 feet up.

Whut the heck?

Powered up and did a careful go-around. Airspeed seemed to work fine on downwind. Established what felt like a normal glide on the next approach. Airspeed did the same thing. Kept a generous speed cushion, just out of caution.

A couple more touch-and-goes (I was enamored by this strange behavior). Taxied back to the FBO, to be chewed out by one of the instructors. "You were flying final way too fast!"

Ah, well.

They did find a bug clogging the pitot tube. Wonder if it happened at altitude, so the airspeed indicator was working like an altimeter as I descended.

Ron Wanttaja

 

[EdFred]

Flew a Citabria for most of my student hours. One day, I was on final. The airspeed started to decrease. I added forward pressure. The airspeed STILL went down. I pushed the nose down as much as I dared, and watched the needle continue to drop. Thought I was going to die.

The needle dropped to zero. Then went past as I shot over the threshold, ~50 feet up.

Whut the heck?

Powered up and did a careful go-around. Airspeed seemed to work fine on downwind. Established what felt like a normal glide on the next approach. Airspeed did the same thing. Kept a generous speed cushion, just out of caution.

A couple more touch-and-goes (I was enamored by this strange behavior). Taxied back to the FBO, to be chewed out by one of the instructors. "You were flying final way too fast!"

Ah, well.

They did find a bug clogging the pitot tube. Wonder if it happened at altitude, so the airspeed indicator was working like an altimeter as I descended.

Ron Wanttaja

Years back I read an article in Flying (I think) where ASI would drop to zero when in a cloud. Out of the cloud it would start to come back to normal. Back into a cloud, ASI slowed to 0. Rinse. Repeat. A bug had started some sort of nest in the pitot and the moisture in the cloud would cause it to swell and block. Getting back into drier air would dry it out and shrink. They didn't die either. Because, well, they wrote about it.

 

[Dan Thomas]

Seriously? Assuming VFR conditions, that seems a bit over the top.

Exactly. Anyone that just has to have an operating ASI, or die, needs more training.

 

[flyingcheesehead]

Wow. Rest in peace, but what terrible accident. A 5000' runway should be plenty to abort your takeoff after you don't see the airspeed moving.

I would have thought the same, until it happened to me. Even with the cover on, there was enough pressure in the pitot that the airspeed came alive, and was close enough to reality that it wasn't noticeable until I was airborne. Landed, took off the pitot cover and picked up my pride off the ground, put them in the baggage compartment and took back off. A good learning experience I guess...

VERY aircraft dependent. In my Mooney, I typically land with full nose up trim. That would make for a VERY EXCITING take off.

Definitely very aircraft dependent, and I fly a Mooney as well, but "exciting" is a lot different from "dead". And our Mooneys behave a bit differently from a lot of GA spam cans - Like we have to trim nose up when adding flaps, for example.

 

[Albany Tom]

I'd bet statistically, it's not checking the fuel level. I always check fuel level first, then fuel sump, then do the walk around, then oil last on the outside. A "flow" if you will. I always check control surfaces, and since taking off once with the trim way wrong, I always check actual, not indicated, trim. For the runup, I'm always careful when checking mags and carb heat. One to make sure I already don't have carb ice, the other to hopefully spot any fouling problems.

 

[darthanubis]

Making sure carb heat is off (on a high DA day). My club lost one of our two planes to this.

I'm a low time pilot. I've been trying to understand when and when not to run carb heat. I've watched a few of Mike Busch's videos on running LOP, and understanding that carb heat makes the mixture richer, so lean for it. My first long XC solo for CPL, over the mountains, then back at night, I flew carb heat on the whole flight and just leaned her out. I didn't want to wait for indications of carb ice, over terrain at night solo. I thought I was being prudent and understood the method of how carb heat worked. Seeing your post, makes me wonder. A recent video I watched of Busch's said, in a 172, the location of the carb on a Lycoming will prevent it from icing when running at power. This was a C172RG I was flying, at 085 full throttle, 2400rpm lop. I forget the temp that day, but it was HOT.

Could you share exactly how the plane was lost to carb heat being ON on a HOT day please?

 

[ja_user]

Trim, Fuel & Flaps... Depending on the plane of course.

 

[flyingcheesehead]

 

[Klaus M]

Took off and flew to three airports and back home. When I got back the dispatcher told me the aircraft was grounded the day before because the Airspeed Indicator was inop. Guess sometimes I need to pay closer attention. I asked the dispatcher why they didn't tell me? "You didn't seem to care when I radioed 'how fast are you going?' ". She said I told her "Don't worry, I'll be back in time for the afternoon flight".

The one word that needs to be added to most pilots check list is: "BREATH". Before Takeoff: BREATH. Before landing: BREATH. Ten seconds, compose yourself, think: what is going to happen next? What If?

If I'm riding with a pilot that's not BREATHING, I ask him 'what did you do last night?'. 'how's the weather?' 'Did you here about (current event or sports)?. The most common accident is getting to tightly wound up in flying and worrying about controlling and keeping up with the plane. Once you're a little more relaxed you remember the fuel selector, carb. heat, fuel pump, landing gear, just: "using the checklist". .... Watch your sight picture.... Eyes out of the cockpit... Communication is second to flying all the time.

No matter how experienced or how thorough you think you are, you can get too focused and loose your scan. Don't think it only happens to the other guy. "I will never do that".
Anybody can get (what's called) "behind the plane".
When you think you have it all figured out, think again. ..... then look around, scan and "BREATH".

 

[wanttaja]

Could you share exactly how the plane was lost to carb heat being ON on a HOT day please?

My guess is leaving it on after a touch and go. Trainer with a full load, high DA, and ~100 HP engine. Sometimes you need that little bit of extra power.

Ron Wanttaja

 

[Mahneuvers]

My guess is leaving it on after a touch and go. Trainer with a full load, high DA, and ~100 HP engine. Sometimes you need that little bit of extra power....

Mostly correct.

@darthanubis, 3090U was a 140 hp 172 carrying an adult male pilot and two teenagers. I flew the plane earlier in the day when the DA was 1.6K and the plane struggled to climb. They asked me not to refuel so it was not a full fuel scenario. It wasn't a touch and go. There were two take offs before lunch. The accident flight was the first takeoff after lunch. The DA at the time of the accident was somewhere north of 2K. Carb heat reduces engine efficiency by ~15%. The NTSB report noted the carb heat and some confusion on the abort point (pilot used the abort point for the wrong runway). No one was seriously hurt but the plane was a total loss. Arm chair quarterbacking here, but the pilot aborted, started decelerating, reapplied power to clear the airport fence, cleared the fence but was unable to stop before the trees. We'd probably still have the plane if he just put it into the fence.

 

[MauleSkinner]

I would have thought the same, until it happened to me. Even with the cover on, there was enough pressure in the pitot that the airspeed came alive, and was close enough to reality that it wasn't noticeable until I was airborne.

The 50/70 rule might have determined that it wasn’t “close enough to reality.” Having 70% of your liftoff speed at the 50% mark in your takeoff roll takes out a lot of ambiguity.

 

[Dan Thomas]

A recent video I watched of Busch's said, in a 172, the location of the carb on a Lycoming will prevent it from icing when running at power.

That is so false it's not funny. I've had carb ice in a Lyc on nice summer days, in cruise. Sure, the carb is mounted on a hot oil sump, but the large amount of air passing though that carb is going to cool it no matter what, and carb ice is possible up to 100°F due to the cooling effect of the pressure drop in the venturi and the evaporating fuel at the nozzle, which can take the ambient air temp down 70° to below freezing, and if the relative humidity is high enough, you get carb ice.

Too many pilots have come to grief because they believed the Ice-Proof Lycoming nonsense.

Could you share exactly how the plane was lost to carb heat being ON on a HOT day please?

Heating the incoming air expands it, reducing its density and therefore the amount of oxygen in a cubic foot of it, so the engine can't make max power. On takeoff this is deadly.

When you ran full carb heat through the mountains and leaned for it, you introduced the risk of engine detonation. Elevated induction air temperatures at high power settings reduces the detonation margins, and leaning the mixture reduces the margins further. Do that in a higher-compression engine and watch it come apart.

Carb ice needs to be thoroughly understood so that the use of carb heat is used in an intelligent manner. But way too many instructors themselves don't understand it, and pass on their ignorance to their students. Not being able to induce ice at will hampers learning about it too. We can stall or spin the airplane, we can cut the power, we can do lots of stuff, but making real carb ice when we need to teach it is nearly impossible.

 

[MauleSkinner]

Could you share exactly how the plane was lost to carb heat being ON on a HOT day please?

How hot is HOT?

 

[chemgeek]

I really wish GA checklists were done better.

No reason you can't write your own condensed and sensible version. I re-organized the AA-5 checklists and printed them out on the front and back of a letter size card stock, placed in a plastic sleeve, that clips to my clipboard. It's set up to make more sense to me and more natural cockpit flow, as well as adapted to my avionics suite and other upgrades since the original was written in 1974. (No need to check the vacuum or set the DG with G5s, for example. And with an LED landing light, no reason not to use it for visibility on takeoff and landing.)

 

[Albany Tom]

How hot is HOT?


View attachment 131534

The humidity today, here where I'm at, is the lowest it's been in 2 weeks. Not exaggerating. The current temp from NWS is 78F, with a 53F dewpoint. That puts us in the yellow zone of that chart, on a NICE day. If you want to learn about carb ice, I'd suggest spending a couple of weeks in this area during the summer....and I'm sure there are other places around the country just as bad.

My 2 cents on cruise carb icing, FWIW: When in cruise, don't f&8k with the power or the mixture after you lean. Watch the RPM. Keep an eye on it if it dips. Don't play with the knobs. If you lose, say, 100 RPM, try out that carb heat knob. If it makes things rough, just like that FAA book says it will, then you're in a good place. Wait until it smooths out, then take it off again. See what the RPM is. What you had before? Then continue. If it keeps making ice, then maybe keep it on. Partial isn't the way to go. None of this invented by me, but learned from folks that have been flying in this area for decades.

The charts are great. When you're a couple of hundred feet under a solid layer, well then that's a clue that ambient and DP are pretty close. If temp and DP are close, then you're probably in the range. Never a bad idea to put in carb heat when you're descending to approach and then landing, at least around here. It's really simple stuff. Don't wait until the engine runs rough before you try carb heat, especially if you have a small engine.

 

[Dan Thomas]

The charts are great. When you're a couple of hundred feet under a solid layer, well then that's a clue that ambient and DP are pretty close. If temp and DP are close, then you're probably in the range.

Yup. The temperature decrease with altitude is about 2°C, or 3.6°F, per 1000 feet. Inside that overcast the temp and dewpoint are the same. 200 feet below it, the dewpoint is 0.4°C (or 0.7°F) below the ambient temperature, prime carb ice territory.

 

[darthanubis]

That is so false it's not funny. I've had carb ice in a Lyc on nice summer days, in cruise. Sure, the carb is mounted on a hot oil sump, but the large amount of air passing though that carb is going to cool it no matter what, and carb ice is possible up to 100°F due to the cooling effect of the pressure drop in the venturi and the evaporating fuel at the nozzle, which can take the ambient air temp down 70° to below freezing, and if the relative humidity is high enough, you get carb ice.

Too many pilots have come to grief because they believed the Ice-Proof Lycoming nonsense.

To be fair to Mr. Busch, he didn't say ICE PROOFED, and I shouldn't have typed "prevents". He said less likely compared to a Continental.

Heating the incoming air expands it, reducing its density and therefore the amount of oxygen in a cubic foot of it, so the engine can't make max power. On takeoff this is deadly.

When you ran full carb heat through the mountains and leaned for it, you introduced the risk of engine detonation. Elevated induction air temperatures at high power settings reduces the detonation margins, and leaning the mixture reduces the margins further. Do that in a higher-compression engine and watch it come apart.

Carb ice needs to be thoroughly understood so that the use of carb heat is used in an intelligent manner. But way too many instructors themselves don't understand it, and pass on their ignorance to their students. Not being able to induce ice at will hampers learning about it too. We can stall or spin the airplane, we can cut the power, we can do lots of stuff, but making real carb ice when we need to teach it is nearly impossible.

My understanding up to this point, is the expanded, less dense air, only enriches the mixture. On the ground or low alt., that almost floods the engine and causes loss of power. At cruise altitude, in a 180hp engine, you simply have to lean back to best fuel/air mixture. Below 75% power, there is very little chance of detonation. Busch also addressed this point in the video online. I'm not a Busch apostate or anything, he just has credentials and experience that I don't. I'm learning from him, and you guys here as I don't have an aviation mentor. The further along I progress, the humbler I become.

Except from an article I'm reading now:

Pilots experiencing carburetor ice should consider landing as soon as possible. If this is not possible and you need to operate with carburetor heat on, then lean the mixture. You should get a slight rise in RPM as you lean. Remember, heated air is less dense. Applying carburetor heat will enrichen the air fuel mixture of the intake air going into the engine. By leaning an engine with carburetor heat on, an increase in performance should result.

Didn't mean to highjack the thread OP.

 

[darthanubis]

How hot is HOT?


View attachment 131534

This is the chart I saw before my flight. It was a yellow zone day and night. I played with the carb ice knob a bit to see if I noticed changes. I couldn't be sure, so I left it full hot, and leaned. Carb ice only off during takeoff and climb out. On the east coast we are currently hot and humid, and stay in this yellow zone. My timebuilding partner doesn't understand this stuff at all, and can't fly the G1000 equipped fuel injected C172 to which we have access. One of us needs to know this, and that me at this point.

 

[flyingcheesehead]

The 50/70 rule might have determined that it wasn’t “close enough to reality.” Having 70% of your liftoff speed at the 50% mark in your takeoff roll takes out a lot of ambiguity.

I don't usually know where 50% of my takeoff roll is when I have more than triple the runway I need... But yeah, good point.

No reason you can't write your own condensed and sensible version.

That's exactly what I do. I just wish I didn't have to, and I wish nobody else had to either. I think what happens is that most pilots just convince themselves that they don't need a checklist at all.

 

[Dan Thomas]

He said less likely compared to a Continental.

Much more accurate. But there are a lot of pilots trained in Lyc-powered airplanes who get complacent about carb ice because it's less common in them, then get into trouble instantly with a Continental.

The Continental C-145/O-300 has a carb mounting similar to a Lycoming. On the oil sump. All others have much colder mountings.

 

[Pinecone]

The 50/70 rule might have determined that it wasn’t “close enough to reality.” Having 70% of your liftoff speed at the 50% mark in your takeoff roll takes out a lot of ambiguity.

The rule is 70% of liftoff speed by the time you have used 50% of the runway.

For very long runways, it is not an issue

 

[MauleSkinner]

The rule is 70% of liftoff speed by the time you have used 50% of the runway.

For very long runways, it is not an issue

The 50/70 rule is based on the physics of airplane acceleration…if it takes 1000 ft to get airborne, the airplane should be to 70% of liftoff speed at the 500-ft mark. Whether it’s on a 1000-ft runway or a 9000-ft runway doesn’t matter.

And if it helps avoid taking an underperforming or improperly indicating airplane into the air, it seems like a good metric to me.

 

[Pinecone]

The 50/70 rule is based on the physics of airplane acceleration…if it takes 1000 ft to get airborne, the airplane should be to 70% of liftoff speed at the 500-ft mark. Whether it’s on a 1000-ft runway or a 9000-ft runway doesn’t matter.

And if it helps avoid taking an underperforming or improperly indicating airplane into the air, it seems like a good metric to me.

Agreed. It was that some people seemed to be misapplying it.

In the USAF we had 1000 foot check speed. That was, at the first 1000 foot marker, there was a minimum speed. If you did not have that speed, you aborted.

 

[ateamer]

The 50/70 rule is pretty darned loose. I fly off of a 3100 foot runway. In the RV-8 at the 50% point, I’d normally have already been airborne for 1000 feet. What I do is pick a spot that equates to roughly 150% of what should be the takeoff roll and use that as the abort point.

 

[MauleSkinner]

The 50/70 rule is pretty darned loose. I fly off of a 3100 foot runway. In the RV-8 at the 50% point, I’d normally have already been airborne for 1000 feet.

Like @Pinecone said, misapplying the 50/70 rule.

 

[ateamer]

Like @Pinecone said, misapplying the 50/70 rule.

Ah, I missed your earlier post - well-worded, makes it clear. I’m adjusting my procedure to use that.