Declared First Emergency

I have seen that video of the pilot saying "vacuum failure" and the controller thought it was a vacuum cleaner. However, "Mayday I have a vacuum failure" still would not mean much to that controller, except that it conveys some sense of urgency. The pilot needs to request no-gyro vectors. My point was that declaring an emergency without a specific request is not always that useful.
Agreed, more info is better, if the pilot isn't fully under the control of their limbic system at that point. But even just "I have a vacuum failure and I'm declaring an emergency" makes it clear to the controller that the pilot needs priority handling.
 
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What are your thoughts on that Mark?
BTDT and wouldn't fly it again without a mechanic confirming what what wrong.
Didn’t we have a POA member who once declared an emergency and after landing took off again and was given a run around by the FSDO?
Had that happen to a client. Not much of a run around though. We satisfied them pretty quickly.
 
On this topic, it's true that the second the adrenaline hits you lose a bucket of IQ points, because your body's redirecting the oxygen from your brain to your muscles, but if you can remember, it's good to assume that ATC knows nothing about your situation and tell them exactly what you need, e.g.

My vacuum pump has failed.
I need to land immediately.
I need to minimize maneuvering.
Landing with a tailwind is OK.

etc.
Speaking from experience, i'd say i'd lost a few IQ points, too. Once i pushed the mixture to full, and the problem repeated itself. What i didn't think about was to pull the carb heat. It didn't seem logical that i'd have icing since i'd not lowered my RPMS to descend from 5500 to 4000.

Today i talked to our A&P and described both the scenario and the possibility of a clogged fuel vent that was mentioned in this thread. That i couldn't repeat the problem on the ground with several high RPM runups tells him it's not the engine, which wasn't running rough. He believes it was probably carb ice and didn't recommend an inspection before our annual which is next month.

He did confirm that the C150 has two fuel vents, one on the left wing cap and one just behind the left strut, and told me how to check to see if the vent is clear. (I checked later and it was.)

So, could i have taken longer to brainstorm the problem? Probably. I was at 4,000 and right next to an airport and on top of a major highway, so i had some time. However, my primitive mind said, "Get this thing on the ground."

Why do i always get FF? Most of the time, i like being on contact with ATC and hearing other aircraft. I also appreciate when they advise me about traffic or ask for me to alter my course or altitude. Still, the ease of declaring an emergency because you have them on the line can not be disputed. I'm glad i was already on frequency.

Brian
 
Carburetor icing can happen at any time when meteorological conditions are ripe. At any light plane altitude and at any power setting. You can Google "carb icing chart" to see the rather broad range of conditions where carb icing is possible. We had a dual fatality in a C-152 operated by a young, low-time pilot who apparently encountered carb icing during a sightseeing flight on beautiful post-frontal fall day, and did not react well to the loss of engine power.

Learn your emergency checklist and/or cockpit flow. It is likely that had our young pilot gone through the emergency checklist/flow, which would have included application of carb heat, an unfortunate accident might have been avoided. When you are flying an airplane and looking for a landing spot after a power anomaly, you don't have time to extensively troubleshoot. Quickly check every simple thing that could be at fault (fuel, fuel flow, mixture, ignition, carb heat). If none of it works, you are ready to land at the safest place you can make it to.

The good news is you made a good decision to make a precautionary landing before things got worse. Use this as a learning experience to hone your emergency response for next time, when the engine may not just surge and sputter, but completely lose power.
 
Speaking from experience, i'd say i'd lost a few IQ points, too. Once i pushed the mixture to full, and the problem repeated itself. What i didn't think about was to pull the carb heat. It didn't seem logical that i'd have icing since i'd not lowered my RPMS to descend from 5500 to 4000.

Today i talked to our A&P and described both the scenario and the possibility of a clogged fuel vent that was mentioned in this thread. That i couldn't repeat the problem on the ground with several high RPM runups tells him it's not the engine, which wasn't running rough. He believes it was probably carb ice and didn't recommend an inspection before our annual which is next month.

He did confirm that the C150 has two fuel vents, one on the left wing cap and one just behind the left strut, and told me how to check to see if the vent is clear. (I checked later and it was.)

So, could i have taken longer to brainstorm the problem? Probably. I was at 4,000 and right next to an airport and on top of a major highway, so i had some time. However, my primitive mind said, "Get this thing on the ground."

Why do i always get FF? Most of the time, i like being on contact with ATC and hearing other aircraft. I also appreciate when they advise me about traffic or ask for me to alter my course or altitude. Still, the ease of declaring an emergency because you have them on the line can not be disputed. I'm glad i was already on frequency.

Brian

Here is a question, do you ever get fuel dripping out of your fuel vent when the tanks are filled to the brim? If not, your fuel vent line could be clogged. I know my vent was clogged for a while in hindsight because I never had fuel drip out of the vent line when I filled the tanks all the way to the brim before taking off on a long flight. After the vent was cleared, I see fuel dripping out slowly if the tanks are topped off and the left wing is a bit low. I just flew today and did a long side slip to landing with tanks that were 3/4 full and after landing had some fuel dripping out of the vent line from the prolonged slip.

SO my vent line was clogged for a long time. Just a few days before my incident, I had an annual and replaced the fuel cap gaskets. I bet that the new cap gaskets sealed better and did not let any air leak past them into the tank. Perhaps that is how the plane was getting its tank venting for a while - though old fuel cap gaskets. Just by changing the gaskets and perhaps tightening the caps, I reduced the air enoug

How did you check the line was clear? Did you blow into it and it was easy to blow air into the tube? You can fill the tanks almost all the way up and have someone up on the wing look and listen to the tank opening and hear you blow bubbles into the tank.

I just know that everyone always blames carb ice and it is not always the case. I looked up the weather for Modesto, CA on November 1, 2020 (just a single data point for the flight) and it was in the 70s with 31% humidity. Watsonville was up to the 90s with 55% humidity or less. That puts the flight most likely in a very low carb ice potential at cruise power. Possible, but not very likely unless the weather was quite different.

For your sake, I would double check that vent because I had the EXACT same problem you had, in the exact same plane and it was a vent issues. The 150 is not going to stay in the air for long with the reduced power of a surging engine.
 
Had a nearly identical experience 28 years ago on my very first flight after my PP checkride. Had wife and dog in a 152 on 3 hour XC when engine started running rough and losing altitude. I did not declare an emergency. However, I did call FF, told them I had a rough running engine, and asked them to vector me to the nearest airfield. They asked if I wanted emergency services to meet me at the field, but by then the engine was running better and holding altitude, so I said no. I landed, found a mechanic, did some ground runups, but could not replicate the problem. I spiral climbed up over the airfield to 6500 AGL, circled a few times to make sure it was running OK, and finished the trip. Chalked it up to either carb ice or mixture error. It spooked me a bit, so I put my wife and dog in a rental car for the return trip.

It's fine that you declared, but I don't think I would have in your situation. I think I would simply have told FF what the issue was, and informed them that I was diverting as a precaution. You have their attention and they are monitoring if things get worse and you have a real emergency, instead of a potential one.
 
I had carb ice a couple of years ago when it shouldn't have happened. It was -18c (which should be too cold), and I was doing the post-maintenance test flight in my PA-28-161 after its annual. I experienced no issues during run-up, made full static RPM on the ground, and had a successful high-speed taxi. I came back around to do a circuit, and at about 200 ft AGL after takeoff — with the throttle wide open — I started losing power.

Carb ice is rare in a Lycoming-powered PA-28, rare at full throttle, and supposedly impossible at -18c in dry, clear weather, but my RPM and climb rate was slowly dropping, so I pulled the carb heat anyway. My engine coughed and sputtered for 10 to 20 seconds, then smoothed out and returned to normal power.

Our best theory is that some moisture must have been in the system from when was in the heated maintenance hanger and it eventually worked its way into the venturi.

There's no way there was enough atmospheric moisture for carb icing on a clear -18c day. But regardless, when you're in the air it isn't the right time for theory — if it walks like a duck and quacks like a duck, treat it like a duck.
 
Here is a question, do you ever get fuel dripping out of your fuel vent when the tanks are filled to the brim? If not, your fuel vent line could be clogged. I know my vent was clogged for a while in hindsight because I never had fuel drip out of the vent line when I filled the tanks all the way to the brim before taking off on a long flight. After the vent was cleared, I see fuel dripping out slowly if the tanks are topped off and the left wing is a bit low. I just flew today and did a long side slip to landing with tanks that were 3/4 full and after landing had some fuel dripping out of the vent line from the prolonged slip.

How did you check the line was clear? Did you blow into it and it was easy to blow air into the tube? You can fill the tanks almost all the way up and have someone up on the wing look and listen to the tank opening and hear you blow bubbles into the tank.
When i asked the AP how to check if the vent was working, he suggested i take off the fuel cap on the left wing, and the blow into the vent tube under the left wing. I did and air flowed freely.

And, yes, fuel dripping a bit after topping off is fairly normal.

Brian
 
There must be some kind of "Bermuda Triangle" thing in that area. Story follows:

My first ever student to get his PP Certificate was a tough nut and he had lots of assertiveness issues. He was timid in all his actions and unsure of everything. Finishing him off and seeing him pass his flight test was a huge triumph and relief for both of us!

After about two months, he decided he would take his father up for his first flight with a passenger. He planned a flight from Concord (KCCR) to Monterey, CA for a lovely lunch with his proud Dad...

Everything went perfect until just about that same ridgeline the OP mentioned. He was still climbing and was below the top of the hill when there was a loud BANG and the engine began running extremely rough, vibrating like hell and spitting fire out the cracks in the oil access door...

He knew that he wanted to be on the ground ASAP and the South County Airport (San Martin, E16) was farther away than Watsonville (KWVI), which he could almost see over the ridge in front of him. After assessing the situation, he determined he still had partial power and was able to cross the ridge and avoid all further terrain in the steep descent to the Watsonville airport. Turning back to E16 would have put him over rough, hilly terrain for several miles befor getting to that airport. Excellent ADM, there.

Now relieved that he was not going to kill himself and his beloved father, he made a CTAF call on the Watsonville frequency and made it know he was heading straight in with engine problems. He was surprised to hear a loud voice tell him to immediately contact the temporary tower for instructions! He had no idea he had wandered into the Annual Watsonville Airshow and the airspace was closed for the Eagles Flight Demonstration Team! Continuing toward the airfield in complete confusion, he managed to switch to the tower frequency and declared an emergency, explaining he needed to land ASAP due to the blast furnace occurring under his engine cowling. This got their attention and the Air Boss immediately called a Knock It Off and instructed the Eagles to abort and circle over the beach.

Once the area was cleared, he was cleared to land on any runway and the crash/fire team was alerted. This news was immediately relayed to the announcer, who explained to the hundreds of spectators that the show was on hold because there was real, no kidding emergency landing about to happen right in front of them!

Once he had the runway made, he completed the emergency procedures, shut down the engine, closed the fuel valve and popped the doors. Imagine his relief!

I wish I could have been there when the entire crowd stood up and cheered as he landed the airplane dead stick and the rescue team pulled him off the runway. When he exited the cockpit with his father, the crowd applauded and cheered loud enough he could hear them.

Needless to say, he demonstrated good decision making, despite having to make the horrifying decision to turn toward the terrain in order to escape the alternative. I'm sure his father was happy with his decision, too!

I got the call to come get him in our club's 172 and flew them back to Concord. They didn't get to have their peaceful lunch on the Monterey Bay, but they have a great story to tell...

The cause of the engine failure was the number three cylinder head blowing off the cylinder and rattling around on the baffle, blowing combustion flames and smoke all over the cowling. I was the maintenance officer for the club, so I had to remove the engine and take it back to the shop that had just overhauled it a month prior.

Maybe there should be a NOTAM...
 
Carburetor icing can happen at any time when meteorological conditions are ripe. At any light plane altitude and at any power setting.

I once picked up carb ice at 10,500' in a C-172 at full throttle on the 180hp motor. Took me a little while to notice, but once I realized what was happening (RPM very slowly decreasing), I applied heat and just like advertised, it stumbled for a few LONG seconds then smoothed out. I re-leaned for the new air density going into the motor and kept the carb heat on until the wheels were on the ground an hour or so later.
 
Had a nearly identical experience 28 years ago on my very first flight after my PP checkride. Had wife and dog in a 152 on 3 hour XC when engine started running rough and losing altitude. I did not declare an emergency. However, I did call FF, told them I had a rough running engine, and asked them to vector me to the nearest airfield. They asked if I wanted emergency services to meet me at the field, but by then the engine was running better and holding altitude, so I said no. I landed, found a mechanic, did some ground runups, but could not replicate the problem. I spiral climbed up over the airfield to 6500 AGL, circled a few times to make sure it was running OK, and finished the trip. Chalked it up to either carb ice or mixture error. It spooked me a bit, so I put my wife and dog in a rental car for the return trip.

It's fine that you declared, but I don't think I would have in your situation. I think I would simply have told FF what the issue was, and informed them that I was diverting as a precaution. You have their attention and they are monitoring if things get worse and you have a real emergency, instead of a potential one.
Just out of curiosity, what do you think the down side is of declaring in a situation like that? You can always end an emergency in the air if the problem goes away (I think there's even official international terminology for that, "mayday fini," though I'm sure something like "situation resolved; end emergency" would be perfectly adequate and maybe less confusing to North American controllers).
 
OP had carb ice. Same damn thing happened to me in my Cessna 150, though I was in a sparsely trafficked area and did hit the carb heat. Thankfully the engine came back as I was on a longish final approach to an airport. Those little Continentals make ice. Good on the OP for declaring and making it down in one piece.
 
The only criticism I have of the OP is that a checklist may have saved him a landing had he used it when the engine started running rough. Remember that.
 
The only criticism I have of the OP is that a checklist may have saved him a landing had he used it when the engine started running rough. Remember that.
Maybe call that a lesson rather than a criticism. It's hard to think clearly when you're under stress, so you get tunnel vision on the problem and revert to the minimum baseline of your training for everything else.

Practicing simulated emergencies using a checklist might help, because then it would become part of that reflexive baseline, even if you're not thinking all that well at the moment. Also, more experience flying might mean that you're less stressed, especially if it's similar to problems you've experienced before, and that will mean you're thinking better in the first place. That's where the number of past "lessons" comes in (we all accumulate a drawer full of those).
 
Just out of curiosity, what do you think the down side is of declaring in a situation like that? You can always end an emergency in the air if the problem goes away (I think there's even official international terminology for that, "mayday fini," though I'm sure something like "situation resolved; end emergency" would be perfectly adequate and maybe less confusing to North American controllers).

Because I believe in being a responsible participant in the ATC system. Part of that responsibility is using good judgement in the declaration of an emergency. Don't hesitate to declare if justified, but also don't declare when unnecessary to deal with the situation. An unnecessary emergency may negatively impact the controller and other pilots in flight. If you gain priority, someone else loses it.

Most pilots do not declare an emergency every time their engine burbles or they suspect carb ice. They evaluate the situation, troubleshoot, and declare an emergency IF the totality of circumstances warrants it.

In this case, the OP was 2 miles from a suitable airfield with plenty of altitude in good visibility. He experienced minor RPM fluctuations with no loss of power or altitude. He made a wise decision to land at the nearby airfield. He could easily have declared an emergency at any point in his approach, should the situation have worsened. It's fine that he did, but IMO was not necessary.
 
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Carb ice is almost an everyday event in the Cub.
Like some guys switch tanks every 15 minutes, I pull carb heat.
On really humid or misty days, the carb heat is always on. We joke that it will make carb ice sitting in the hanger.
Franklin engines and Continentals are equally bad, On the Cub the Lycoming is not quite as problematic, but still makes ice.
 
Carb ice is almost an everyday event in the Cub.
Like some guys switch tanks every 15 minutes, I pull carb heat.
On really humid or misty days, the carb heat is always on. We joke that it will make carb ice sitting in the hanger.
Franklin engines and Continentals are equally bad, On the Cub the Lycoming is not quite as problematic, but still makes ice.
Whether or not something is an emergency isn't absolute — it depends on your experience and qualifications.

Flying in cloud (on an IFR clearance) is a common occurence for me, but if a new VFR pilot wandered into cloud and couldn't easily exit, that's a bona-fide emergency.

You're used to carb ice, so it's no big deal for you (and so, a non-emergency), but the number of fatal accidents attributed to carb ice suggests that a successful outcome is in doubt for many pilots who encounter it without your experience, and as soon as the successful outcome of a flight is in even small doubt for that pilot, it's an emergency.
 
Whether or not something is an emergency isn't absolute — it depends on your experience and qualifications.

Flying in cloud (on an IFR clearance) is a common occurence for me, but if a new VFR pilot wandered into cloud and couldn't easily exit, that's a bona-fide emergency.

You're used to carb ice, so it's no big deal for you (and so, a non-emergency), but the number of fatal accidents attributed to carb ice suggests that a successful outcome is in doubt for many pilots who encounter it without your experience, and as soon as the successful outcome of a flight is in even small doubt for that pilot, it's an emergency.

This is most certainly true.
I climb in the Cub, and I'm looking for carb ice, so carb ice prevention is an automatic response based on years of experience.
About 6 years ago I had an engine failure in a P-92. I had pulled the throttle to start a slow descent, and turned on the fuel pump and carb heat, as per the checklist.
The electric fuel pump flooded the engine.
I was down 2,000 ft before I even realized the engine had stopped running because the prop was windmilling the entire time.
I was surprised and embarrassed to be caught like that.
Lucky I had started at 10,000 + ft, or this could have gotten really ugly.
I was able to glide 6 miles and make an engine out landing at 44N. I didn't even bother to declare an emergency on the way down. I knew I could make the field, and I had practiced engine out situations in that plane a hundred times.
I'm convinced that in a lot of incidents, it's the surprise and lack of experience that kills most pilots, which is exactly your point.
Practice everything
 
There must be some kind of "Bermuda Triangle" thing in that area. Story follows:

My first ever student to get his PP Certificate was a tough nut and he had lots of assertiveness issues. He was timid in all his actions and unsure of everything. Finishing him off and seeing him pass his flight test was a huge triumph and relief for both of us!

After about two months, he decided he would take his father up for his first flight with a passenger. He planned a flight from Concord (KCCR) to Monterey, CA for a lovely lunch with his proud Dad...

Everything went perfect until just about that same ridgeline the OP mentioned. He was still climbing and was below the top of the hill when there was a loud BANG and the engine began running extremely rough, vibrating like hell and spitting fire out the cracks in the oil access door...
Thats a great story. Thanks for sharing. I got my PPL at KCCR through PSA in the late 60s.

Brian
 
Last time I declared and made a precautionary landing for an engine problem the fire Captain offered me a ride home. No paperwork.

Don’t forget that declaring lets you do whatever you need to get on the ground safely. Not declaring is the same mentality as not filing a NASA form—it can only hurt you.
From all the reading i've done since coming back to flying six years ago (I took 40 years off for life.), i learned that it's always best to declare if you need it and that there's rarely paperwork afterwards. That i had ATC's attention and help, even if briefly, was reassuring.
 
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The only criticism I have of the OP is that a checklist may have saved him a landing had he used it when the engine started running rough. Remember that.
I can't dispute this. Only afterwards did i notice that in ForeFlight's checklist section are several nifty Emergency checklists for occasions like mine. Yes, i could have been better prepared in my plane's emergency procedures.
 
Sounds like run-of-the-mill roughness from forgetting to richen things in the descent to me. Have done that a couple of times, just corrected the mixture and continued with the flight. Never thought to declare an emergency :p
 
I can't dispute this. Only afterwards did i notice that in ForeFlight's checklist section are several nifty Emergency checklists for occasions like mine. Yes, i could have been better prepared in my plane's emergency procedures.

Lesson learned, but you handled it well, kudos.
 
Sounds like run-of-the-mill roughness from forgetting to richen things in the descent to me. Have done that a couple of times, just corrected the mixture and continued with the flight. Never thought to declare an emergency :p
But "sounds like" is a dangerous attitude when things start to go wrong. If the problem does not resolve itself in the first 10-30 seconds of running an emergency flow, you have a real emergency, regardless of if you can eventually figure it out or not.

I was flying at only 2500' AGL over almost completely forested terrain with the nearest airport 10 miles away and had a similar issue as the OP. Engine surging 1000+ RPM over a 5 second interval and continuing with no improvement using throttle, mixture, carb heat, mags. The mighty C150 will not hold altitude without a majority of its power, so we were going down at a steady rate, the question was how fast. Without an immediate decision of turning back to an airport and declaring Mayday to get someone to know where we were and what we were doing, we would have been landing in a too-small wooded clearing at best. Did the fuel vents in the caps eventually pass enough air to allow us to make it back to the airport, yes. Would we have made it if the airport was 15 miles away? Don't know. But my fuel vent line was totally and completely blocked - like could not get air in there even if you had a compressed air blower.
 
But "sounds like" is a dangerous attitude when things start to go wrong. If the problem does not resolve itself in the first 10-30 seconds of running an emergency flow, you have a real emergency, regardless of if you can eventually figure it out or not.

No, you have a real emergency IF you have a real emergency. That requires good judgement in the evaluation of total circumstances. Your story is a good illustration of that. You were experiencing large power fluctuations, losing altitude, at low altitude, over hostile terrain, and out of glide range from the nearest airfield. The OP was experiencing small power fluctuations, not losing altitude, had plenty of altitude to troubleshoot, and was easily within glide range of a suitable airfield. Most pilots can evaluate the two situations and see the difference in urgency.
 
Yea if OP has an 0-200 those babies put a Maytag ice maker to shame . I fly her sister the c85, I pull the old heat now n again every flight...often with zero symptoms but just to make sure they aren’t creeping up on me...
 
You did a fine job!

Now, later in the week don't forget to tell us about the infamous "mountain of paperwork" you faced as a result :D
In my experience, "mountain of paperwork" is a myth worthy of dying one day. I've declared emergency way more than 50 times in 22 years of flying fighters in the military and almost never (one instance) had to do more than tell my side of the story over a phone call. I will NEVER delay saying the E word just because I think it might cause some paperwork. And whenever I did say the E word, I got nothing but the best help from ATC.
 
In my experience, "mountain of paperwork" is a myth worthy of dying one day. I've declared emergency way more than 50 times in 22 years of flying fighters in the military and almost never (one instance) had to do more than tell my side of the story over a phone call. I will NEVER delay saying the E word just because I think it might cause some paperwork. And whenever I did say the E word, I got nothing but the best help from ATC.
Your experience is the same as others who have declared emergencies. Too bad myths don't die easily.
 
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