Unsolved To This Day: Oregon's Worst Air Crash | West Coast Airlines Flight 956 

I really love how you always end the video with the intended landing approach of the flight it's about, it always gives me mixed feelings

My personal belief? Cockpit confusion seems the most likely scenario. With the DC-9 being a very new aircraft, and the crew's experience thus being on different aircraft, it's entirely possible that they accidentally carried out a procedure for an aircraft they were more familiar with, instead of the DC-9. The pilots may also have been distracted by something happening within the cockpit, and not noticed the altimetre passing their assigned altitude. Unfortunately... you're correct that we'll never know. With the CVR destroyed, we'll never know what was being said in that cockpit.

I have something to add to the cockpit confusion theory. You stated that they were cleared to 9000 feet, yet their altimeter was set to 4000 as I recall. Depending on their gauges and angles of viewing those instruments - I wonder if they accidentally set it to 4 instead of 9……and it looked like a 9 when viewed at an angle. Interesting crash which is not too far from where I live.

Like everyone else in the comments, I have to echo the "cockpit confusion" and "misread altimeter" theories. The Series 10 DC-9s use a drum-and-pointer altimeter that's been implicated in a number of other crashes in various planes, and this particular drum system was especially bad because of the small size of the actual numbers and the lack of showing the numbers above or below the displayed one except on the 100s drum. Later variants and many of the surviving examples of the Series 10 either came with, or were retrofitted with, a more modern digital drum or at least a drum with larger numbers, the altimeters are fairly inconsistent between photos simply due to how many of them were swapped over for other kinds. If the altimeter wasn't confusing, there wouldn't be so many retrofits of other altimeters in surviving or documented examples.

I really love these explorations of older, lesser known, regional airline incidents.

I routinely fly with captains and first officers alike, we fly heavy jets and we do long haul flights, although not the same type of operations, I have witnessed some of these crewmembers place a wrong altitude in the altitude window, and call the wrong number as the correct number while pointing at the wrong number, what's worst, the other flying crewmember repeated the correct altitude number (value) while looking and pointing at the wrong number that was placed in the altitude window, only to be corrected by the other pilots or the same pilot that had placed the wrong number in the altitude window. The DC-9's of the 1960's had a "Drum Type Altimeter" and by design it was difficult to "read" the altitude and easy to make a mistake. I do not know the type of altimeter that this particular DC-9 had installed when they suffered the CFIT. I believe that it could have been a combination of these factors or both or just one of them, either way, it was a deadly result. RIP to all involved.

My guess: 4,000 was mistakenly selected as level-off because a 4 has some resemblance to a 9 (upside closed loop and right-hand-side vertical trait). If something was momentarily distracting the Captain who set it, he might not have looked at it long enough to see the difference.

I knew Capt Aldrich, his son Kirk was my classmate in Boise. This the first I knew of his death this way. I'm abit in shock right now. I don't believe Don could have been at the controls cause he had been flying this area since the early 50's out of Boise. He flew with my Dad out of Boise on Empire Air which with Mohawk became West Coast. He was just too familiar with the area to have made a turn into the mtns. It must have one of the others. What was their flight experience in this area.

An old maritime saying: "The ship with two captains always goes down." I wonder if the 4 0n the altitude select was confused as a 9.

I have a theory about this. They responded “Roger descend to nine, leaving one four.” This is non-standard phraseology and probably caused the accident. Usually you would say “Leaving one four thousand, descending niner thousand”, and then you would reach up and set the altitude, which would be the same number stated at the end of the read back. They reached up and set 4,000 in the altitude selector because “4” was the last number in his read back, and he was distracted enough to dial in 4,000 with neither pilot catching the mistake. In summary, they accidentally set the wrong altitude, didn’t catch the mistake, and it all stemmed from a non-standard read back. Thoughts?

never knew of this crash, but, I have once had an eerily similar accident in a simulator (the plane was a derivative of a DC3 Cargo, so, somewhat different, but a vital part (the altimeter) I think was thesame) this is what happened... according to the scenario, we were flying a fire-crew from the fire-marshal base at "Roseburg Regional Airport" to Portland, conditions were scattered clouds and mist, considered IFR bellow 11 thousand, with smoke also further obscuring visibility... our approach was fairly well into the mountains to avoid nasty weather in the valley, with a plan of turning onto final just east of Dodson. our altimeter told us we had just come out of 9'000 feet (descending to 8000) when we saw a ridge of under 5000 (45.29, -122.04) rise up ahead of us... in the debrief afterwards it turned out, the difference in barometric pressure near the mountains compared to the airport had basically gave us a reading some 4000feet above where we were.... this is why when flying in these parts you need multiple methods of reading the altitude... not just barometric... these ridges do things to the air pressures...

If they tried to set the auto-pilot to descend down to 9,000 it's entirely possible that they simply set it to 4,000 by mistake. 4's and 9's look extremely similar on older style displays. Anyone who's owned an old alarm clock with the 8:88 style display has probably made a similar mistake at least once.

Hi, I agree with the "misreading the altimeter" theory. This one sounds to be the most plausible one. A silly mistake, which noone bothered to cross check and then it proved fatal.

The captains set 4 instead of 9. they look similar on appearance in analogue systems used back then. The pilot turning the knob didn't pay much attention so he saw a 9 but it was actually 4. So he ended choosing 4000 instead of 9000.

Chain of events that went wrong. Have you ever looked at united airlines 409? It's an older accident but interesting. The Merrill family was on it. There's still wreckage of it in the Medicine Bow mountains. Wasn't even supposed to be in that area. Thanks Mini! As always another great video.

"It probably wasn't a sterile cockpit."

With a new aircraft, familiar results to certain inputs could vary. For example, the pilot knows without thinking that turning the altitude knob a certain amount will result in a ~5000' decrease in altitude so he spins the knob, glances at the readout and see what he expects to see - a decrease in the setting from 14,000' to 9,000'. But on this new plane, when you spin that knob the same amount as before, the result is nearly double that of the earlier model, so instead of ~5k' change there's a ~10k' change. When the pilot glances at the readout he mistakes a 4 for a 9 as that is what he expects. The attempt to level off at the end testifies to their realization of continued descent and the start of corrections. Why didn't the voice recorder function? Was it damaged in the crash or was it simply not working?

It is 1960s technology without a radio altimeter so they are relying on barometric pressure for altitude and the air pressure may not be what was expected. In which case they may well have been according to their instruments dead on 9000 feet. Normal air pressure at 4000 feet is 656 mmHg and at 9000 feet is 543mmHg it is not that big a difference weather and mountains could possibly cause that much pressure change. Presumably the altimeter is calibrated to the air pressure / altitude at the departure airport which may be very different.

I was around in 1966, I was in high school at the time. A few years later I was working with a commuter airline that had a working relationship with Hughes Airwest. In July of 1968 West Coast Airlines merged with Pacific Airlines and Bonanza Airlines to form Air West. In 1970 Howard Hughes bought the airline and it became Hughes Airwest. The crash of flight 956 was still fresh in the minds of my friends working for Hughes Airwest and they had definite opinions on what caused the crash. They felt that when ATC told the pilots to turn right to 3 0 0 it caused confusion because normally going into PDX they usually made a turn to the left to stay clear of Mt Hood and then turned right after they were clear of the mountain. The flight was in IMC during the approach into PDX. Radar altimeters were not in widespread use in DC9s at the time. As you noted the DC9 was a new aircraft type for West Coast Airlines at the time. The DC9 had just entered airline service in the U.S. in December of 1965 (with Delta). Before the DC9 West Coast Airlines was flying DC3s and Fairchild (not Fokker) F27s. It was the F27 pilots who were transitioned to the DC9. So up until the arrival of the DC9 these pilots were flying the F27. When the DC9s entered service the DC3s were retired and the airline flew a fleet of F27s, DC9s and Piper Navajos (from 1967).

Flying in 1966 wasn't what it is now. It is quite possible that the crew believed they were on the approach and thus could descend to the IAP (3700'). This was a common assumption in those days. Terrain was not shown on approach plates then. There were no moving map displays, GPS, GPWS, and much more. The accident that changed the thinking on this, along with the phraseology of approach clearances controllers issue, was TWA 514, which crashed on Mt. Weather in Virginia, USA, on December 1, 1974.

Great analysis-I am a mountain guide in the area and was hired by an aircraft crash hunter into the crash site in 2007. We found the crash site but also found a downed military helicopter on the same ridge. We also found a downed weather Balloon transponder on the same ridge. My theory is severe downdrafts in that area. I researched the internet and could find no reports of a military crash in that area.

I remember the old, noisy helicopters flying over my school bringing the bodies down to PDX. I was in elementary school. Second grade. Spooky. Sad.

Misread altimeter was a very common problem with the 3 pointer unit.

If this was a check flight, there’s a good possibility that it was being hand flown. If they were casually chatting about stuff (very common back then), it would be easy to lose track of the descent.

There are some parallels between this and the TWA flight 514 accident in 1974. TWA 514 descended below cleared altitude, likely due to confusion between the crew and ATC. Fortunately, 514 had a CVR so there's a better understanding of what took place. en.wikipedia.org/wiki/TWA_Flight_514

Well, in my view, cockpit confusion might be the reason. As you told, plane was nose up means tried to save the accodent, experienced crew will not make such a mistake of keep decending without contacting tower so, only thing left is theory no. 3.

i love your videos, as I don't have time for long videos. Gr8 job.

I have been to this crash site a few times, the wreckage is still there, as well as the small clearing it made. It's sad to think of the lives that were lost there.

This is a little bit before my time but I had an uncle who was waiting for this aircraft in Portland. We are from Yakima and he was heading home via Seattle. This was still remembered years later after West Coast became Airwest. Unfortunately although I remember the grown-ups talking about the crash I don't remember hearing any cause except it flying into a mountain.

I really appreciate the way you're not afraid to end on a "here are the theories and evidence for and against, but we just don't know". That honesty and courage to not sensationalise these incidents makes your videos feel very trustworthy.

Your last theory makes sense plus the difference in panels of DC9. I don’t recall hearing if these pilots had flown into Portland from Eugene on a regular basis which would be informative. I’m another Oregonian and may query folks. Thanks for your great production!’

I did some checking on this flight.. while the pilots had thousands of hours flying, in total they had only 76 hours on this plane. I would think they'd have at least one pilot with more hours. A side note, 3 of the 15 passengers were employees of the same airline.

The only jet at West Coast Airlines was the DC 9. They were mostly flying TURBOPROPS (Fairchild F-27s ). I don't know enough about the technical differences. But we should really be reading the crews 17, 50 or 9 hours in a DC-9 as max *50 hours in a jet.*

Thank you for these videos. My guess is they set the auto pilot to 4000 from 14000 by accident on a new airplane?

The cockpit confusion theory has some merits. Most likely many of those thousands of flight hours were accumulated over years of flying prop and turboprop airplanes which many at the time had a flight engineer to manage the systems, and things in a jet are a bit more complex and things happen faster. Additionally, this DC9 may have been a "baby 9" (-10 series) which was a little bullet, lacked slats, and anti-ice systems worked much different than deice boots, for example. We owe the many safety improvements of today, with radio altimeter, TWAS, EGPWS, to the many crews and passengers lost in those early days of jet aviation, which in some ways were really pioneers. RIP.

Theory no.4 - I worked at the PDX airport for another airline, and I heard that it discussed, previous to this crash, the following. This was a brand new airplane and it was West Coast first jet. The company was very proud of this step into the jet age, and I heard ( I cannot recall where ) that on previous flights the cockpit door had been left open in order to allow company employees and others to inspect the cockpit while in flight. I recall that it was said that it was kind of a festive occasion for employees and others ( and maybe the crew ?) I have wondered for years if distraction might have played a part.

I think it's in your description...the pilot said back to the controller, "9,000 ft...leaving one four thousand feet". When he said out loud (one) "four thousand feet", he input 4,000 ft. He probably made that mistake in that moment and was onto his next task. The autopilot levelled off at 4,000 ft, which he had mistakenly set the altitude at.

I really enjoy your videos

This is simular to the AA accident in 1959 with the brand new Electra with FC DeWitt in command in to LGA. The same type of CFIT was the accident of BU239 23rd dec 1972 from AES-FBU. It was the first leathal crash with the Fokker F-28. Great vlog as always!

Hello buddy greetings from Andrew Sydney Australia , looking forward to watching this after this long add,

As I'm from Switzerland, I'm aware of the Alitalia Crash in 1990 near Zurich, where misreading the altimeter was a major factor

My first thought is they were confident to the point they "knew" where they were that double checking wasn't even a thought. They probably had the flight path memorized.

Theory number three is my uneducated guess, thank you for another excellent episode Sir!!!🙏✈️😢

Really good videos! Do you fly? Keep these coming? I’d love to see your take on the 1950s Grand Canuon collision!

Unfortunately, having technical issues with individual aircraft new into service, rather than aircraft types new into service, is far from unusual, even today, and was probably more common back in the '60s, so it could be that the pilots were somewhat involved in handling a technical issue and, with the aircraft making its' descent in a desolate area with a lack of visual clues to their position, lost spatial awareness of their position until, unfortunately, the mountain became visually apparent, by which time the crash was probably unavoidable, even though the pilots appear to have continued to fly the aircraft right into the impact. It could, however, be argued that the decision by West Coast Airlines not to specify their aircraft with radar altimeters, particularly when they operate routinely in areas of high terrain, could be said to be a causal factor in this incident... I have to wonder if the, at the time unusable, CVR was retained after the investigation was completed, as it might be possible to forensically recover data from it now that would not have been possible at the time. If, and it's a big if, all these things aligned, and if someone was prepared to put the time and money into reading the CVR then it might be possible to find something that does shed more light on the situation at the time. It does, however, seem unlikely that the federal government would be inclined to do anything regarding a crash that happened in the mid-'60s now, so it's probably going to remain uncertain...

You missed 3 major things: 1. DC-9's autopilot didn't change altitude. The pilot had to do that. 2. The 3 pilots were NOT trained. The captain had 17 hours experience flying a DC-9. First officer? 9. Check captain? Only 50 hours. They should not have been flying yet. 3. This was the company's first ever jet. What I think happened is something like this: 1. The pilot-in-command (PIC) likely had the other pilot set his altimeter alert. It was the only thing they had to tell them they were too low. 2. The person doing it put it to 4,000 feet. Maybe they couldn't see (I believe it was one of the only kind of LED thing on the control unit) due to a glare, and thought 4,000 was 9,000. It was also only a single dial you spun - maybe leaving 14,000, the other pilot just blanked and put 4,000 due to being preoccupied with other stuff. 3. PIC trusts his other pilots so he descends. It's the company's first jet (all other planes were prop), so they likely descended far faster than they were used to and didn't even realize. 4. Altitude alert goes off making them level at 4,000, before they realize their mistake. The engines weren't idle so I imagine it was full power to try and avoid it. Sadly, it takes something like 8 seconds for a plane to respond to inputs. And that's it. The DC-9 was advanced but it wasn't perfect. It held an altitude and speed like a car's cruise control, but you had to get there. There wasn't a ground proximity alert system yet - it took a ton of these controlled flights into terrain in the 60s to develop it. So if no pilot flying really understood how a jet responded and they relied too much on autopilot, then... this.

Legend has it that Angry Gremlins were at the controls of this plane.........Damn them little critters !!!!!

I had the opportunity to sit in a real DC-9 cockpit a while ago and I talked with a (now former) DC-9 Pilot. My theory: They dialed in 4,000 instead of 9,000 ft in the Altitude warning of the Autopilot since 4 looks strikingly similar to 9 when seen from a distance. The DC-9 autopilot is slightly different to a modern autopilot. It doesn't level off automatically at a preselected altitude. Basically you put the Autopilot into vertical speed and the airplane climbs/descends at that vertical speed until the DC-9 either stalls or until it crashes into the ground. It doesn't level off on it's own. The altitude selection window is only for the warning sound. So you would set it to the altitude you're climbing/descending to. Before you reach that altitude a warning tone will sound to remind you to manually adjust the vertical speed on the small vertical speed wheel of the Autopilot or the DC-9 will bust right thru the altitude you wanted it to climb/descend to. So how does it come that both pilots (all three to be exact) seemingly overlooked the altimeters right in front of them ? Quite easy. Depending on what type of altimeter was installed on that particular DC-9 misreading the older style altimeters is something that has happened in the past (not just in DC-9.) There were three different types of altimeters that could possibly have been installed in that DC-9. If it was that kind of altimeter, that I think it was, The drum type altimeter then i could absolutely understand that the pilots misread the altimeter and didn't notice that the were descending to 4000 ft, the whole time until the plane leveled off and they looked closely at their altimeters. If the DC-9 was really fitted with that two digit Drum type altimeter I believe was fitted or even worse the three pointer altimeters (if they were ever fitted in the DC-9 ??)then I can imagine what happened. I think that they didn't realize something was wrong until it was way to late to prevent the disaster. So my theory is the following: -The Pilot monitoring correctly Undestands the 9,000 ft altitude limit. He intends to put that altitude in the altitude selecting window for the altitude warning. But inadvertently puts in 4,000 instead of 9,000, since the small altitude window is on the F/0 side, below the engine instruments and next to the F/O's knee. So it's harder to reach (compared to today's autopilot panels) and it's definitely harder to see. So thinking 4 is 9 is not to far fetched. -the airplane starts descending like it's supposed to, so nothing would warn them that they dialed in the wrong altitude for the warning tone. -the two drum type altimeter is hard to read (compared to other altimeter designs) and it's In fact the most prone to misread altimeter design of all possible altimeter designs. An altimeter, like it's used today, could be ready by a 5 year old. 32680 is 32,680 feet. Easy. But a very tiny #9 for indicating 9,000ft could be overlooked when the drum is slowly turning, in a dark cockpit. It was October so it was already dark outside. So except the panel and instrument lights a dark cockpit. The dimly lit #9 for 9,000ft comes and passes. The plane keeps descending. The pilots had no reasons to look more closely than normal to their altimeters. They thought they had set the warning to 9,000ft ! So they expected the warning to sound, telling them that they were nearing 9,000ft, while in Reality they were already descending well below that clearance limit. -both pilots talk about the approach, about the new airplane, they glance at their altimeters every once in a while. But none of them is looking closely enough and long enough at the small number in the small rotating drum to 100% identify the real number the altimeter is actually indicating. -finally the altitude warning sounds, signalling that they are nearing their selected altitude. -one of them turns the small vertical speed wheel to slowly decrease the rate of descent to level off at the altitude, so that the airplane is perfectly level at 0ft vertical speed when the large needle of the altimeter hits the 0. -once again they concentrate on something (but not the right thing), this time it's n the big needle of the altimeter indicating the hundreds of feet. Not on the small and difficult to read drum that indicates the thousands of feet. -the plane levels off and the pilots continue to prepare the approach, still trying to get familiar with their brand new flagship. While simultaneously talking to ATC. The autopilot of the DC-9 is reliable. Why shouldn't they trust their new brand new airplane that's just 15 days old ?!? They had no reason not to trust their new airplane. -suddently one of them sees something out of the cockpit Windows, something like the shadowy and Dark outline of the mountains in front of them and he looks at his altimeter. But this time more closely and concentrated or by pure coincidence he just looks this time closely at the altimeter for whatever reason. -the answer of the altimeter is simple: 4,000 feet and not 9,000 ft is Indicated as #4 on the small drum. The pilot seeing this is shocked. All of them know about the terrain. Just 4,000 ft altitude in an airplane in that part of Oregon is asking for big trouble. A quick glance at the radio altimeter is even more frightening. The needle of the radio altimeter is not just already visible (it's already well below 2,500 radio altitude above the ground where the needle becomes visible. Infact the needle is fast turning towards 0 feet above the ground. -a fast and violent pitch up is made, the throttles are firewalled, all in a last attempt to prevent the inevitable. But it's already to late. In those two remaining seconds will the airplane neither climb significantly nor will the engines spool up fast enough to produce the power needed for a terrain escape maneuver. Personally I normally don't like speculation. But having had the opportunity to fly the DC-9 in a simulator, talk with a real DC-9 pilot and while training to get my own PPL, this is the only reasonable conclusion that would explain every detail of that accident. Why they descended so far below the altitude they we're cleared to, Why they we're totally oblivious about it and talking the whole time with ATC as if everything was fine and why the airplane leveled of at 4,000ft. In my opinion, This is what really happened on West Coast 956 on that fateful evening. The captain had just 17 hours experience in the DC-9. The Check captain sitting next to him just 50 hrs. And the F/O in the jumpseat behind them just 9hrs. All three of them were extremely new on the DC-9. So making such an easy mistake doesn't sound to far fetched, especially if all of them are new on the type. Remember GPWS came in 1974. EGPWS only in 1998. So there was nothing that would have warned them in time to realise their mistake before they impacted the mountain.

Maybe it's because I was born in Portland that makes it seem incredible to me that anybody could have been oblivious to the significance of Mt Hood. As it's such an awesome mountain.

Fantastic video! I’m going to say the most likely theory is someone just messed up with such a new cockpit, it makes the most sense to me!😸

Very sad loss of life and experience, even a simple oversight can take the most experienced of us. Rip to all.

I like number three. Too much skill can make you cocky. Nice new plane, maybe the scenic approach ? The more fun mountain skimming arrival ? Makes me think of the crew who took their plane too high for fun. You can imagine. Turn of the recorder and "let's see what this baby can do " !

You can make a video about every crash and chances are that we'll watch all of them

My guess is they mistook the 4 for a 9 when setting the autopilot. Depending on the font used I can see them looking similar enough. And if they hit turbulence or were just distracted by The beauty of the PNW it could’ve been that simple. Sad. Thanks for your report!

Please make a video on the Ariana Afgan flight 701 which crashed on approach to London Gatwick

My theory about what happened is this, the pilot monitoring read back the ATC as one four thousand, instead of FL140. Perhaps they knew roughly where they were, but the pilot flying, preoccupied with slowing the aircraft and setting up the turn to 300 degrees, only heard the four thousand part, and set the auto pilot to that altitude. I honestly cant think of anything beyond that being the cause of this crash

I got my pilots license in 1965 in Springfield OR and was in Civil Air Patrol. Our squadron had connections with squadrons and the Air Force Base in Portland area. Mountains and topography was shown on flight maps. This may have been the inaugural passenger jet flight out of Mahlon Sweet Airport in Eugene, on the flight were many of the business people who promoted & assisted in upgrading runways and terminal at the airport. My understanding of the circumstances was somewhat different. On approach the traffic controller told them to turn right for a west bound approach to PDX, the pilot questioned the right turn, expecting a left turn, the controller confirmed right turn. At the time going against ATC instruction involved a lot of paperwork and penalties, so the pilots complied, especially on IFR flights as this one was. It was also my understanding that this was a new approach procedure and new routing for a commercial jet as they were the first jet flight out of the newly expanded Eugene airport. Several local businesses were severely crippled for a few years due to loss of leadership. Most had their spouses with them on this 'champagne' flight. Terrain detection, ground radar and such was much more primitive than the equipment and procedures available today. Electronics were still in vacuum tube technology, circuit boards were 20 or 30 years in the future. Glide slopes were new systems not available at most airports, altho PDX did have it on some of its runways. Transponders only told position but not altitude, speed, etc. Computers many years later would put that at fingertips of controllers. Plus I don't believe individual planes could be identified - pilots were asked to 'ping' their transponders to make a bright spot on radar screen. My personal opinion is that ATC thought they were on other side of airport and were trying to get them back on track. Radar wasn't 100% reliable then either. That and there were not the rules nor understanding of effects long hours would have, so back to back shifts for both ATC and pilots was common. We've come a long way.

I go with misread altimeter theory. One year previous to this crash, a United Airlines plane ( idk aircraft type or flight number), crashed into Lake Michigan mere miles from the Chicago shore. It was due to land at OHare only 15 minutes later. It was determined the pilot misread the altitude of 500 feet to be 1500 feet. It was night, so no visual view could be made of the lake. This flight is very similar.

If you're from the Pacific Northwest, as I am, running into one of the majestic volcanos would be very strange. They are prominent features of life in the region. I suspect cockpit confusion related to the newness of the aircraft.

My late father flew Dizzy-9 for American Airlines, and I wish he were here to comment on this event. Being completely unfamiliar with the navigational instrumentation of this plane (and the era, for that matter), one wonders if the flight elevation for the autopilot was “dialed in” to a specific setting using analog technology, or was it a digital display, where the numbers 4 and 9 are “box” numbers and can be misread. Regardless, these were top-notch pilots with very little “time on type” experience of this brand-new aircraft. It only takes so-many steps before you fall into an irreversible disaster. We can only hope that the airline industry learned from this tragedy.

A DC-9 does not have an autopilot that can automatically level off the aircraft once it reaches it's commanded altitude. The next best thing was to put in your desired altitude to the 'altitude alerter,' which would beep and flash to alert you when you were approaching your target altitude. Then the pilot would have to level the aircraft off manually. I've never flown a DC-9, so I can't speak to how loud or bright that system was, but if it malfunctioned or wasn't noticed for some reason, I could certainly see distraction or an over reliance on new technology contributing to the accident.

Another theory to add to the pile (which has already been stated in the comments, but I'll second the motion): A closed-top 4 and a 9 in certain fonts aren't *that* different at a glance, so in low lighting conditions might have been confused on the autopilot's altitude input. Alternately, depending on what the interface looks like, the more digital 4 and 9 found on most calculator or alarm clock readouts are only differentiated by a single line at the top or bottom. So, slightly different from miss-reading the altimeter, it's possibly whoever input the new altitude simply pressed the wrong button, and then the flight crew started going over an approach briefing to satisfy the check captain onboard, and as a result just didn't notice until either they began receiving terrain warnings or the mountain entered visual range.

I was 7 years old. Great video friend.

under certain conditions figure four can look like figure nine - from the corner of your eye (e.g.) new aircraft, the unfamiliar layout of the cockpit! so put that with Benjamin Finlay's equation. we have a very plausible explanation.

Well, I don't believe it was deliberate. Sometimes, "too many cooks spoil the brew".... The other day I had four guys in the cockpit each checing each other. This made me nervous, a distraction from the normal flow of duties, and each might have assumed one of the others had performed a specific task. I think it is like you say, confusion with the latest cockpit updates/changes on the new plane led to not knowing the actual altitude. May they all rest in peace

Just an observation @ about 4:35 you say that they were directed to turn Rt1 to 300deg - should be rt turn to 030 degrees… great video though, always love your stuff

Reportable there is still some wreckage up on mount hood but it is advised to not disturb it because the park service says that could be considered as a grave site for the victims

The last time I was this early, 737 MAX was still grounded

It’s quite straightforward. Whoever configured the altimeter did the damage, when they were cleared for 9000 ft and the the one who handled the radio communication with ATC read it back ending with 1 4000 ft, so in misunderstanding the altimeter was set to 4000 ft instead. I hope this makes sense. IMO, Read back with “Leaving 1 4000 ft” is redundant. “Cleared for descend to 9000 ft” conveys the message. Never bother about the previous state.

The first dc-9 crash had a stop over in Eugene why i am I just learning this now

The theory that makes the most sense to me is the cockpit confusion one. I initially thought that it could have been fatigue, but as mentioned, they crew had adequate rest. The intentional act theory makes no sense to me either. Let's fast forward about 42 years to the Aeroflot 821 disaster in September of 2008. Neither pilot of Flight 821 were highly familiar with the 737 as they had both had much more experience on Soviet planes. Also, let's explore the AIRES Flight 5280 case, where those pilots went from turboprops to a 737 quickly, and although it was an illusion that caused that disaster, I am sure that the different cockpit fueled the confusion. Going back to the deliberate act theory, as you said, why would one pull up if they wanted to crash on purpose? Looking at LAM Mozambique Flight 470 and Germanwings Flight 9525, once the pilots of those planes were alone, they saw the chance to leave the controls alone and intentionally let the plane impact terrain. With those cases in mind, cockpit confusion is very likely.

How about this theory? They were originally cleared to 14 thousand feet, and probably had that number in the auto pilot. When they were cleared down to 9000 feet, they started to change the autopilot setting to 9000, which got rid of the "1" but left the "4" when they were interrupted with the right turn heading change, which they questioned. In other words, they left the altitude setting in the autopilot at 4000, and the plane automatically descended to that, while they were busy with other actions in the cockpit (the right turn, preparing for approach and landing) and by the time they realized it (and leveled off) it was too low to clear the mountain.

One possibility I considered is that the numeral 4 and 9 can look similar on blocky displays. If they weren't familiar with the instruments they may have made this mistake.

I should listen carefully again. Having done some flying in the Portland area, the radar vector from ATC does not make sense. In my thinking, they would be on a heading close to due north, a left turn would be roughly a 60° turn, whereas a right turn would be about 300° and take them away from the Columbia river valley, roughly parallel to the runway. The top of Mt Hood is above 11,000 ft. I listened again. On my phone screen I couldn't make out much detail on the approach chart in the video. For sure they descended way too low. But the right turn still seems wrong to me, and as you mentioned, also to the pilots. I can't imagine with the combined hours of the flight crew they lacked situational awareness so much. What your video did not state was the position of the plane when told to turn right to 300. If the accident report included the enroute navigation from Eugene, that would be another puzzle piece.

There is one crucial piece of equipment this aircraft did not have which was not even mandated to be put in aircraft until the early 1970s and that is the Ground Proximity Warning System. GPWS

I agree with Joel Brown below. I think they inadvertently set the altimeter to 4000 ft vice 9000 ft.

Another excellent video.

I loved your video You’re really in the groove now. I admire how you and your channel have grown. (Not time to switch on your auto pilot just yet however you’re doing really nice investigations so good ) Stay VFR for now Your future look s good 👍 This video 10 out of 5 stars ⭐️⭐️⭐️⭐️⭐️ ⭐️⭐️⭐️⭐️⭐️ Best wishes always from Las Vegas Craig Bravo 👏🏻

My 1st thought was with so much experience in the cockpit, it can lead to an over relaxed environment. Also can result in extra chatter. Unfair and I may be completely wrong.

A thought. After controllers gave directions to descend to 9K, potentially it was written down and then when it was time to descend, the written 9K was mis-read as "4K". When written, 9's and 4's can be misinterpreted depending on how they are written.

Excellent Work, bordering on Scholarship! (As an aside, MyBeloved Father, and some of his close associations, told me, more than once, of their low opinion, of the DC-9! Soooo many problems! And always,the same 'story', blame the pilots and/or the maintenence-crew. Yet, when finally, it came 'down-to-it', in subsequent investigations, it turned out, that the DC-9, had massive design-flaws! Remarkably, even with much corrobrating evidence, some will STILL defend it! Much like the Airbus of today, despite its many crashes and failings and recalls! Amazing!) Again, Well-Done!

Three-Pointer Altimeters. They were a killer to interpret in a fast intensive landing situation.

Nice job on your vids very good work .. Im going with door # 3

Isn't it amazing that the most experienced crews are involved in so many air incidents.

Fascinating. My first though when I saw the PNW was weather - I'm near the Canadian border so it's commonly cloudy with bad vis. But, it sounds like confusion with the new DC-9/misreading the altimeter. Plus, CRM wasn't used at that time. Two captains with lots of experience and no CRM could contribute to miscommunication, even with the best of intentions.

Synopsis Probable causes 1. Flight crew error due to poor training on this particular plane. Amicable solution Safety management systems that put an emphasis on proper Theoretical and practical training.

my theory is that something distracted them or they put 9000 ft in the autopilot but never selected the "hold altitude" botton or like someone said accidently selected 4000 instead of 9000 and so they began carrying out the pre-landing checklist, and when the plane leveled off at 4000 and they saw the mountain coming closer, they turned and tried to go full power but as we all know engines dont react immediatly from idle to full power, it takes time. but it was already too late when they pulled the nose up bleeding precious speed and the plane then impacted the mountain

Mt Hood peak sits at just over 11k feet. Hood river/ white salmon gets intense fog, so I see what you mean. Overall another great video!

Blowing an altitude is something that's happened more than a few times. Couple that with an unfalisr airplane and I would guess that's what happened. Also, the altimeter installed can, and does create confusion...Pan American, Caracas, 1989.

I wonder if they kept the remains of the cockpit voice recorder. What was impossible to recover in the 1960s may be recoverable today.

Just a point for your consideration, as well as mentioning the total time for pilot experience, you should mention the pilot's time in type, and what aircraft the bulk of their experience was in. As is obvious from the statement of how new the DC-9 was, it is highly likely that the crew had almost no time on the aircraft, and all their experience was in older types.

"This... is the story of..." And I'm hooked.

Here in Argentina there is a legendary rock band (Los Redondos) which has a song called Flight 956, but the lyrics have no relation with this crash...

It was probably an entry error with the autopilot. 4 and 9 are similar looking numbers at a glance. They probably entered 4000 instead of 9000.

I'm no pilot and don't know what the display for setting altitude is like on this type of aircraft, but if it's digital, I may have a theory as to why they descended to 4000 instead of 9000. Take a calculator and key in the number 94. Now, what if the top LED wasn't working? The 9 would be displayed as a 4. If that happens on only the 4th digit from the right, 9000 becomes 4000. If the pilots believed, or even knew that LED was faulty, they would expect to see 4000 displayed instead of 9000. Long shot, but I wonder if such a minor thing was checked. It wouldn't be the first time a faulty light caused a crash. (Eastern 401)

What a sad mystery. At least we know that plane wasn't as full of people as it would be nowadays. Also in those days, situational awareness wasn't such a big concern. Those pilots had alot of hours of flying. They probably flew during WW2. Sometimes, as we know now, being too relaxed or over-confident in the cockpit, especially in a new plane, can lead to devastating problems. It seems to me that their problem came about rather suddenly. Which leads me to believe that they were not paying attention for whatever reason. I hate it when we don't know the answers for sure!! Dang!

Hey, look forward to your vids always 🎉🎉 So, without long explanations etc. , logic suggests your last theory of the plane being new and the pilots not fully aware of their new instruments .... cheers to you 👍

Theory 3B: Confusion in the Cockpit. Cockpits are notoriously cramped. Having 3 people trying to manuever in the cockpit instead of two caused some control to be knocked out of its setting, and they did not notice for a few moments, when they were already too close to the ground.

Thanks for your work

this sounds like a miss read of the altimeter, it sadly happens, especially near mountens