Super glad we weren't on any of these flights. As for the passengers who were, sometimes ignorance truly is bliss.
The Best is Left Unknown

“Half the passengers in this story had no idea, while the other half likely crapped themselves. My father was a captain for Eastern Airlines and told a story about almost being at takeoff speed when another commercial jet taxied across his runway. He was going too fast to abort so he had to pull up early and cleared the other plane by feet (don’t remember the exact amount). His passengers had no idea but the other plane’s passengers saw everything. I don’t know what ended up happening to the other pilot, but my dad got an apology call from him that evening.” Source
Failing Under Pressure

“I’m a commercial airline captain on a newish embraer 175. Probably one of the scarier things I have had happen was when one of our cabin pressure control channels failed and we started to rapidly lose pressurization. Pressurization is important because the air is so thin in the flight levels, specifically above 30,000′. The higher up you get the less ‘time of useful consciousness’ you have, down to about 30 seconds. So it’s a pretty scary thought and it’s a problem requiring immediate action, usually a steep emergency descent, during which you will not hear from the pilots because we are suuuuuuper busy. Our pressure controller has two channels and automatically switches to the second if one fails. We were flying along, about to start our descent and briefing our arrival, and our ears started popping like mad. I looked over and the pressurization was climbing very fast. We started a steep, but not quite emergency descent, while I flipped the pressurization switch to manual and then back to auto. This manually switched the channel to the working one and we could continue without problem. Pretty sure all the passengers noticed their ears popping. It gave us about 80 seconds of a scare though. The funniest part was that when we landed our maintenance control wanted us to ‘defer’ the pressurization channel over the phone, meaning we will fix it later (generally a very safe way to get flights out on time with something minor or redundant broken). I told him I was going to have to insist that someone come over and actually look at the plane to say it was safe to fly.” Source
NORDO!

“I’m an air traffic controller. Had a pilot go NORDO (that’s when, for whatever reason, they aren’t on my frequency anymore. They didn’t get the right one, misheard, or their radios crapped out). It happens fairly often, and there are a number of things we can do to get you back in the right place. This particular guy, however, went NORDO at precisely the worst time. He was going eastbound, which means he was at an odd altitude. He lost his radio, and his flight plan then had him turn southbound. That means he was supposed to be at an even altitude, which he obviously wasn’t. There were about a dozen different planes going northbound that were at his altitude, so he ended up running one heck of a gauntlet through all these people as I was descending and climbing them to get them out of his way. Then, apparently in an act of sheer ignorance on the pilot’s part, he decided to choose an even altitude all by himself, knowing he should probably be at one. Remember all those planes I had to move out of his way? He managed to put himself right back into them. When you have closure rates of over 1,000 knots an hour, that’s not a lot of time to react to those things. At the end, my butt was clenched so tight that when I stood up, the seat came with me.” Source
Someone Has A Lot of Learning To Do

“Currently a flight instructor. Had a near miss a month ago. I was in a practice area with a student pilot who was performing steep turns. Our standard procedure is for both pilots to look in the direction of the turn and state clearly ‘clear right/left’ before even dipping a wing. Well, it had been a long day and I was getting pretty tired. As the student pilot prepared to start his turn I casually glanced to the right and said, ‘clear to the rig–holy crap never mind my flight controls.’
A Cessna caravan from a nearby charter company was passing within a hundred feet of our right wing and the turn would have taken us directly into him. My student never even saw him. In any case, it shook me up pretty good and taught me an important lesson about not getting lazy with clearing procedures even after a long tiring day. Fortunately I still looked, and so the clearing procedure essentially worked as it should have by keeping separation, but I shouldn’t have even begun saying the phrase ‘clear right’ until I had carefully examined the air next to us. Little things like that can kill you in this industry.” Source
Complete Engine Failure

“Airline pilots generally inform passengers on a need-to-know basis. If there is a malfunction the passengers can’t see, hear or smell and if it doesn’t have an immediate effect on the flight it is best not to tell anything as it can only cause panic.
(1) The closest I’ve come to a disaster was almost a decade ago when during cruise the thrust reverser suddenly unlocked on engine 2. This was one of those near hypothetical failures we trained for in the simulator but you’d never expect to see in real life. We immediately pulled that engine back to idle because should it fully deploy on cruise power the resulting yaw motion could easily cause structural damage (Lauda 004 and TAM 402). Playing with the throttle we found that the ‘thrust reverser unlocked’ warning only appeared at a high power setting. After a short consult with maintenance we decided to leave engine number 2 running at low power: allowing us to continue the flight to our destination, while not being at risk to overstress the airframe should it deploy. Shutting the engine down completely would have meant we had to divert to an alternate airport because the remaining engine can’t provide enough power to generate the electricity, pressurization and thrust required to continue to our destination at cruising altitude.
Passengers may have noticed a reduction in engine noise from the right-hand side of the aircraft and a slight delay, but apart from that there was nothing that could indicate something was amiss.
(2)Piloting a small aircraft for a sightseeing flight with 3 passengers I once experienced an engine failure. This was partly self-inflicted and a valuable learning experience. 5 minutes in flight I saw the right fuel tank was empty. Because I’ve looked in the tanks before departure and as the indicators are far from reliable I suspected instrument failure over a fuel leak. Letting go of the controls the aircraft flew straight and level as you’d expect when having 2 equally filled tanks. Still, I’d rather be safe than sorry so I decided to lean the fuel/air mixture a bit to optimize fuel economy (Generally the fuel mixture in an aircraft’s piston engine has a bit more fuel than required for combustion. The evaporated non-combusted fuel cools the engine from the inside). Keeping an eye on the engine temperature I started reducing the mixture when suddenly the engine stopped, the aircraft went completely silent and started to glide. Pushing the nose a bit to keep the propeller windmilling I applied the emergency checklist from memory and the engine roared back to life at full mixture. I told my passengers I had to shift gear, while they remained completely oblivious about what just happened. Back on the ground we found that one of the 2 magneto’s providing electricity to the spark plugs had failed.” Source
A Close Call

“Not a pilot but I’m an air traffic controller and have had my fair share of near collisions. Less than a week after I got certified, I had the closest call of my career….
It was the end of a swing shift on a Friday night with just myself and my watch supervisor. We were waiting for a formation flight to come in and land for the night. Near the end of the shift, we received inbound information on them and a few minutes later they tagged up on radar, marked overhead (landing maneuver) and full stop. For those who don’t know: an overhead maneuver is a type of tactical approach very common in the military. It is basically a descending 360-degree turn that starts over the approach end of the runway at an altitude of 1,500 to 2,000 AGL and is complete when the aircraft is established on final. Anyway, the formation was 4-mile initial for the overhead when approach control called up with a medevac helo 15 miles north east inbound with a critical casualty requesting transition through our airspace. Given the relation of my two aircraft and the position of the helo, I told the approach controller ‘transition approved, you guys can keep them (on comms), our aircraft are going to be on the ground in a minute.’
My aircraft begin their tactical maneuver to land and I give them their landing clearance. Not worried about the situation, I turned around and chatted with my supervisor about what we were doing that weekend. I glanced over and the first aircraft was turning his base-leg to land and assumed the second aircraft behind him would do so as well shortly.
Our conversation ended abruptly by the sound of our radar’s PCAS (alarm), alerting us that a collision was imminent. I looked at the radar and the second aircraft and the helo were nose-to-nose, less than 1 mile apart, at the same altitude. I keyed up and gave a traffic alert to which I recieved a short pause, followed by a calm “we see ’em.” The targets passed over one another with the indication of the same altitude, which means they came within 100 feet of one another.
What happened? I learned 3 things from this incident.
First and foremost, never get distracted in side chatter when you have aircraft you are responsible for. The formation in the overhead: the first aircraft conducted the maneuver as published, the second aircraft made a 180-degree turn, flew 5 miles, and then made a second 180, before descending; which was not typical. Anticipate aircraft not conducting the maneuvers as usual. The MedEvac helo was going much faster than I anticipated. Typically, these helos fly around 80-90 knots. This helo was traveling at about 140 knots so I anticipated the aircraft not being as close as he was. Always look at the airspeed of a transition.
I worked at a very busy training base and incidents were fairly common, typically 2-3 a month. It depends on what you would consider an ‘incident.’ Due to the nature of the traffic flow, we had separation busts all the time(IFR vs. IFR), however, we would very easily fix this with various turns and other procedures.” Source
She Was Oblivious

“I used to fly vintage biplanes and take people up on ‘joyrides’ effectively. We would do aerobatics, let them fly it for a bit, and come back for tea and medals. We also did air displays and we did wingwalking (although my DA didn’t allow me to do those)
While its not your typical airline passenger transport, it is still commercial flying!
As these aircraft were built in the 30’s/40’s, there was several times where the sh_t was hitting the fan, and as the cockpits are separate, they were blissfully unaware. Always was a chuckle at the end having to explain that what just happened wasn’t normal!
Some good examples:-
Engine exploded during flight (big end failure, blew a hole in crankcase), landed in a field. Passenger was french and just thought landing in a field was what we did at the end… He couldn’t understand the mayday on the radio.
We used to land on a grass runway, had a tyre blowout (one and only time), we mustve stopped in about 50m (normal run on is about 200m ish). Passenger had no idea until I had to get fire crew out to help push aircraft back to the hangar and he thought the whole thing was great.
After of the many engine overhauls, one of the first 5-10 flights afterwards, flight was normal, we always did a bit of aerobatics as we were all qualified display pilots/aerobatic instructors. I come up to the top of the loop, start to pull the throttle back and it goes loose in my hand, I am stuck at 100% throttle. The stampe throttle linkage is designed to go flat out if the linkage snaps(it is counterweighted so gravity keeps it at 100%). Said nothing, quietly informed ATC I would need runways clear as I was going to dead stick it from overhead. Chopped the engine at 2000ft and just did a tight glide approach in. Luckily had a multitool so I just jury rigged the throttle back once we had stopped, started the engine (it had an air start), and taxied back and got it fixed properly.
Most of the time, the passenger doesn’t know what normal is, so its no different for them when things go awry, assuming you get a safe landing out of it. Source
The Landing That Shouldn’t Have Happened

“My father is a commercial pilot and has been for decades. Used to be a 747-400 co-captain, then a 757 captain, not really sure what he flies these days.
Anyway, a couple years ago he was very upset at exactly what this post is asking. He was in Brazil, or Buenos Aires, or some such place (South America) and on takeoff, the tire blew. It ripped a giant hole right through the wing of the plane. He had to dump thousands of gallons of fuel and managed to land the plane. The write-up that made the news was something like, “A plane had to do an emergency landing after an event today, no one was hurt.”
HOWEVER, all the mechanics and people involved said they absolutely couldn’t believe he managed to land that plane in the condition it was in. They claimed he should have crashed and couldn’t believe it. He was very angry that they didn’t tell the passengers and didn’t want to fly again for a couple months. He was very shaken. He even sent the pictures to me of the damage and said I should leak them somewhere… but, the fact is, no one cares.” Source
Loss of Power

“My friend was a co-pilot on a commercial flight I was on from Toronto to Los Angeles and it was the scariest flight I have been on and getting the co-pilot’s perspective after the flight made it even scarier.
The flight went very smoothly until we were making the decent into Los Angeles airport (LAX) just after 10-PM. I was looking out the window and it seemed as if we were 20 metres from touching the runway when all the lights began to flicker and the plane went into complete darkness! Immediately, you could feel and hear the engines thunder into overdrive and we pulled back up.
Plane continued rising and we began to circle the air in complete darkness as everyone begins to share concerns. The flight kept circling for about 20 minutes before the pilot came on explaining they were having some technical problems, and they are discussing with the ATC to resolve the issue and make a safe landing. The circling in the air continued for nearly an hour but it seemed like an eternity in pitch black. Lights never came on, and we were notified we were going to make an attempt to land. People say this all the time but I can assure you, THIS was one scary decent! The bumpiest decent I have ever been part of. We were constantly being lifted from our seats, the seatbelt light really had merit this time. People were screaming each time and I was actually holding onto the arm rests and we kept defying gravity and swaying left and right. When we saw the lights on the runway inch closer, the plane slammed onto the runway and we once again heard the engines roaring as we slowed down on the runway. As we came to a stop, the plane just stayed there and waited on the runway for a tow to the docking area. You could feel the relief within the cabin. If everyone was sitting on toilets, I can assure you, each one would need a flush.
After we arrived, I met with the Co-Pilot a few hours later, as we had planned to meet for a day before he had to fly out of town. He explained they lost electrical power and had lost several forms of communication and flight information was not available to the pilots. Ultimately, the pilots had to land the plane manually with nearly no assistance or outside help. Considering it was night time, poor visibility and limited flight information available, this made for a very sh_tty landing. He admitted as well it was the scariest flight he has been on.
Tops my list of Moments I thought I was dead.” Source
“Canada has an Air Force, eh?”

Well, it was a 2 seat Cessna and everyone involved knew what happened, but here we go.
This was years ago and I had taken the chance to fly back from Alaska to the Lower 48 in a Cessna 150. This thing was basically a riding mower with wings. 17 year old me thought that it would be fun to take longer flying the distance than driving it (which was true in terms of time, but that was because of storms that grounded us in BC for 2 days).
We were flying into a regional airport in the north (name not given to protect the involved). It was a standard X-shaped 2 runway affair, with 3 controllers and a supervisor in the tower. We are on base approach, tooling along at about 75 mph, and watching for other aircraft. TeenMe is thrilled to see a pair of FA-18 Hornets from the Canadian Air Force also in the pattern. After the obligatory jokes about “Canada has an Air Force, eh?” we concentrate on landing.
Now, the 150 we were in has a stupidly short landing distance, so we are on the ground fast and just derping along to get to the taxiway. After 3 hours in this tiny plane, I take off the headset to try and get comfortable. Thus, I don’t know what was said by the tower, but the pilot goes white as a sheet. “OH F_CK.”
All of a sudden, we are turning around on the runway, which is NOT something that is EVER supposed to happen. Confused and terrified, I start to ask what is going on when I look up.
At a distance of “Too F_cking Close” are the Hornets. Flaps and gear down, going right over us.
They go to afterburner and go around as our Cessna putts over and parks. Dead silence in our cockpit. We stop, tie down everything, and stand there for a second. “Pilot, are you ok?”
“Yeah…. are you ok, Bronan?”
“Yeah. Did that just happen?”
Any further reply is stopped by the sounds of idling jet engines. The Hornets are on the ground and parking. They get out of their planes and do their checks. They powwow for a minute and then all 4 come over.
Wait, 4 you say? Yeah. These were trainers. 2 new pilots, a new back seat… and a Full Bird Colonel to supervise.
They walk up, and the pilot and are having visions of getting torn a new one by the long arm of the Canadian Law.
“You boys ok, then?”
Nervous laughter is shared by all and the Colonel says “Lets go have a chat with the tower, eh?”
I was thus treated to the very first experience of getting reamed by a staff officer that I have ever seen. The controller failed to pay attention to our relative speed and stacked us WAY too close together. That officer was NOT happy and he let everyone in the building know it. We were excused, shot the breeze with the other pilots for a bit and continued on to America. Still probably the closest to death that I have ever really been. Source