Ok I’m gonna info dump about Cactus 1549, aka the Miracle on the Hudson, because I watched a really cool video about it and want to share what I learned!
Quick summary for anyone who may not remember: On January 15, 2009, an US Airways Airbus A320 departed New York’s LaGuardia heading for Charlotte NC, and shortly into the flight encountered a flock of Canada Geese. The strike caused the loss of both engines, leaving the plane with no thrust at an incredibly low altitude of ~2800 feet.
Here’s what went down:
- The pilots reacted super quickly. And one thing the Captain, Chesley “Sully” Sullenberger, did immediately, even though it wasn’t on his checklist yet? Was switch on the APU. That’s the Auxiliary Power Unit, the little extra engine at the back of the plane that can supply the plane with power. Remember that ‘cause it’ll be important later.
- The APU gave the plane back its electrical power, but they still had no engine thrust, which means they were now effectively a giant glider over one of the most densely populated cities in the world.
- They radioed ATC for a heading back to LaGuardia--in other words, directions for which way to turn to get back. They were given heading 220, but as they began to turn, Sully was doing some mental estimations. He realized they were too low to make it back to LaGuardia on a glide. (And later, it was determined he was correct: while the plane could have technically made it back if he’d turned instantly, it was ultimately decided that such a turn would’ve given him no time for reaction, assessment, or decision making, and that is incredibly unrealistic. He made the right call.)
- He asked about another possible airport--Teterboro, in New Jersey--but quickly decided it was too far away as well. When offered a runway at Teterboro by ATC, he famously replied with one word: “Unable.” And then the famous words: “We’re going to be in the Hudson.”
What happened next, in summary: they glided to the Hudson, the plane didn’t sink, the passengers evacuated, and a bunch of Hudson river Ferries and scuba cops from helicopters were able to rescue everyone. Of the 155 passengers and crew on board, all 155 survived, with the worst injury being one of the crew receiving a laceration on her leg.
Here’s why this is such a miracle, though.
- Water landings almost never go this way. For EVERYONE to survive is basically unheard of.
- But this particular Airbus A320 happened to be equipped for extend over-water flight. The slides were slide-rafts, meaning that once deployed they doubled as rafts. Every passenger had their own life vest.
- This was TOTAL coincidence. The plane was bound for Charlotte then Seattle--meaning no extended over-water journey was expected. That they used this specific plane was a total lucky chance.
- When an incident occurs on a plane, the First Officer is supposed to check the QRH--Quick Reference Handbook. There are instructions for basically what to do in almost any conceivable circumstance. First office Jeff Skiles had just gone through a course on the Airbus A320 a few weeks prior to the incident, meaning he was more recently trained than most about exactly where that QRH was, and where to find what he needed.
- One issue the pilots faced--they were actually dealing with 2 issues at once: a double engine loss, and a ditching. Ditching is an emergency landing of the aircraft. Skiles appropriately turned to the dual engine failure checklist, but in doing so, they missed out on a few of the crucial instructions that were in the ditching checklist.
- Most notably, the instruction to disable the GPWS--Ground Proximity Warning System. Planes have all sorts of warning systems that yell instructions at the pilot, but the most important tends to be the one that says “don’t crash into the ground.”
- So the overriding warning, the one that drowned out all others, was the one saying “Terrain. Pull up. Terrain. Obstacle. Obstacle.” Which...yes. Duh. We’re ditching the plane, of course the ground is getting close, right?
- One of the changes made after this incident was a checklist that combined dual engine failure with ditching--because teh assumption prior was that a dual engine loss would occur at high altitudes, not at 2800 feet.
- Anyway. Because the GPWS was yelling at them, it was drowning out another critical warning: the low speed indicator.
- Sully thought he was maintaining an appropriate speed in their approach to the river, but they were actually going just a little too slow. That means that when Sully attempted to flare the plane--pull the nose up right as they were landing--he could have caused the aircraft to stall.
- Remember how I said it was important that he turned on the APU, even though they were nowhere near that instruction in the checklist?
- This caused the aircraft to stay in what’s called “normal law,” where the computer has enough power to stay in control of the plane, and override certain pilot commands to prevent negative outcomes, like, say...a stall due to low speeds.
- Without the APU, the computer would’ve been in Alternate Law, and Sully’s attempt to flare the nose would have been allowed, potentially causing a disastrous stall.
- But instead, normal law overrode his command, and prevented him from flaring the aircraft to the point that it would stall out. This is actually why there was damage to the rear of the fuselage (the body of the plane)--they hit at a less than optimal angle. But without the APU, they could’ve stalled, and that would’ve been much, much worse.
- Turning on the APU has now been put at a much higher spot in that checklist.
- And then after hitting the water, they just happened to be in an incredibly busy part of the Hudson river, where there was plenty of help available.
So to sum up:
1) Experienced glider pilot happened to be flying a plane with 2) a copilot who happened to have just undergone a training that made him fast at finding what they needed in the QRH, in 3) a plane that just happened to be equipped for a water landing, 4) over one of the busiest waterways in the world, 5) and said pilot happened to do something that wasn’t on the checklist yet and that prevented the aircraft from stalling.
This is why they call it the Miracle on the Hudson. Not just because everyone involved behaved in exemplary fashion and performed their jobs with exceptional professionalism and skill, but because all of these other factors came together to put every possible thing in the right place at the right time to make the outcome what it was.
Ironically, we should be calling every successful flight where nothing goes wrong a miracle, because it is--a miracle of engineering, performance, CRM (Crew Resource Management), maintenance, and care--but then we’d be calling millions of flights miracles, and I guess after awhile we get bored of the mundane miracles.
Here’s the video I am essentially regurgitating for anyone who wants to hear a (more accurate and detailed) telling from one of my favorite youtubers!
I really like airplanes. Passenger airliners to be precise. Thought I’d let you know.
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