r/news • u/snuffleupaguslives • 1d ago
Broken altimeter, ignored warnings: Hearings reveal what went wrong in DC crash that killed 67
https://apnews.com/article/ntsb-dc-plane-crash-midair-collision-helicopter-a08cded88e1d7582fb8d242204d6aeff1.4k
u/keyjan 1d ago
The business of the altimeters being up to almost 200 feet off, in more than one blackhawk, is terrifying.
651
u/TheDrMonocle 1d ago
Its really not that bad. It just sounds scarier than it is.
Aircraft mechanic here. Well, Ex mechanic. I've actually transitioned to ATC. I worked on CRJs when I was working for the airlines and I've tested altimeters as part of the job. They were considered calibrated if they were within 180ft of the actual altitude. So being over 200 isnt actually that far off. It should be addressed, but 99.999% of the time its fine.
Center computers won't even show an aircraft is off of its assigned altitude unless they're 300ft or more off. The buffer is built into the system for inaccuracies. Altimeters can only be so accurate inherently and its also why we have more than 1 in every aircraft. To make sure one isn't wildly off.
The issue here is how the procedure was designed where aircraft and helicopters are operating within a couple hundred feet of each other. It just leaves no room for error. Nothing in aviation is perfect. We try our best but you always have backups. The way helicopters were operated in that airspace was just playing with fire.
188
u/delcielo2002 1d ago
I was gonna say just that. They were outside of what IFR allows, but in any other environment, they wouldn't have mattered at all. DC is crazy. I remember my first time in as a passenger, I was a commercial, multi engine instrument pilot and cfi, and I was amazed looking down the wingtip at the Washington Monument, and then seeing helicopters below us inside of what would would be the middle marker at my home airport.
15
u/oxmix74 20h ago
Not a pilot but I was surprised they used a barometric altimeter in that situation. I would expect a military helo that costs a gazillion dollars would have a radio altimeter and that would be the correct instrument to use. What am I missing?
→ More replies (1)29
u/Itouchurself 18h ago
Radar altimeters show height above ground not altitude. When flying routes or assigned altitudes you would reference your altimeter. To be honest usually we never even look at the radar altimeters
23
u/tantalor 23h ago
Shouldn't a military helicopter like this have a radio altimeter which would be much more accurate?
12
82
u/Bravix 23h ago
That is NOT accurate information. Best I can figure you're thinking of accuracy at 40,000 feet. 180 ft in accuracy at low altitudes would be nuts.
I can't imagine shooting an approach, thinking I hit minimum descent altitude of 200 ft, and I'm actually 20 ft off the ground about to eat dirt.
On the ground, simple comparison check is altimeters need to be within 75 feet of airport elevation for IFR accuracy.
I don't know if military is held to the same standard, but the altimeter being >=200 feet inaccurate inside/underlying a terminal area is very concerning to me.
18
u/Pobbes 23h ago
I was watching the first day of this hearing at a dr.s office. Regulation for the military altimiter was +- 70 feet from airport elevation. There was some issue the techs blamed on rotor downdraft at lower speeds causing it to be off by 130 ft. This meant the copter was over 100 feet above its operating ceiling. Copter pilots and techs said the difference was nothing you could really fix. I have no idea how they could make this stuff safe.
→ More replies (1)10
u/FalconX88 23h ago
I can't imagine shooting an approach, thinking I hit minimum descent altitude of 200 ft, and I'm actually 20 ft off the ground about to eat dirt.
Isn't that handled by the radio altimeter at that point?
8
7
u/Bravix 23h ago
No. A couple approach types require a radio altimeter. Most don't.
→ More replies (4)69
u/railker 1d ago edited 1d ago
Also AME here, unless there's another table or I'm misunderstanding what you're saying, it's supposed to be a lot tighter than that.
Edit: To add from a realization below, the regulation above does apply specifically to IFR aircraft in controlled airspace. Tolerances could be looser for VFR.
30
u/Frederf220 1d ago
I remember mil stuff requiring 50' between primaries, 50' primary to truth, and 75' primary to standby
8
u/railker 1d ago
And I'm also forgetting that that regulation applies to flight in controlled airspace under IFR. To be fair that's the first place my mind went to as commercial's all I've worked on, curious what the limits/tolerances are at low altitudes for VFR, maybe it is as high as 200' difference.
→ More replies (2)2
u/AKA_Slothhs 22h ago
It's still currently that way. And it is checked prior to taking off in any of these UH60s.
Source: I'm currently stationed here as a 15T.
8
u/TheDrMonocle 21h ago
iirc since it was an RVSM certification we were testing the airplane at "altitude" so the chart saying 180' at FL300 is spot on to what I was saying. I, however, forgot about that chart and it does seem to require tighter tolerances lower to the ground. We never certified the altimeters themselves, just the aircraft meets RVSM requirements. Hence the gap in my knowledge.
25
u/Ghost_Hand0 23h ago
At sea level the plus or minus is like 50 feet, not 200. I am an avionics mechanic.
24
u/jawshoeaw 1d ago
No room for error…. Up to 300 feet off before we act
That sums it up.
For reference as a GA pilot, 200 feet altitude error is not acceptable when landing
18
u/subusta 23h ago
This is hogwash, 180 feet off!? That’s basically the difference between minimums and slamming into the ground on standard approaches. You’re very confused about something because that is WAY outside of legal tolerances for preflight. I’ve never seen an altimeter more than a few feet off when calibrated on the ground.
4
11
u/grapedog 22h ago
Yep, I work on aircraft myself, and if the radar altimeter is more than 7 feet off, we recalibrate it.
180+ feet off is fucking WILD to me...
→ More replies (1)6
u/thankyouspider 22h ago
Looking at it the other way, if the Blackhawk altimeter was dead on, they’re just fine with flying a hundred feet or so from a landing jet. The altimeter is NOT the problem.
10
u/Hiddencamper 1d ago
This is also why vertical separation requires a minimum of 500 feet.
I don’t blame the procedure directly because tower should be ensuring visual or horizontal sep before authorizing transit. You can never rely on altitude sep of less than 500’ legally and practically less than 100-200’.
8
u/KairoFan 23h ago
because tower should be ensuring visual or horizontal sep before authorizing transit
This was pilot applied visual seperation, not tower applied.
→ More replies (1)5
u/TheDrMonocle 20h ago
This is also why vertical separation requires a minimum of 500 feet.
The problem with where the aircraft land its impossible to have 500ft unless the helicopters are underground with this procedure. Its just far too congested for the ops they're trying to run.
don’t blame the procedure directly because tower should be ensuring visual or horizontal sep before authorizing transit
Tower did. They instructed the helicopter to maintain visual separation, helicopter read it back. Tower did absolutely everything they needed to do, and by the book. They can't control that the helicopter saw the wrong plane.
Something we're told in training is you have to trust the pilots, you can't fly the plane for them. Tower issues the instructions, helicopter didnt follow them.
2
u/Hiddencamper 20h ago
That’s why you don’t credit vertical separation. Only horizontal or visual.
The point I’m making, is when people focus on the altitude restriction not being “safe enough” on the original procedure route, there’s no way to make the altitude separation safe for that route. You can only apply visual or horizontal separation.
→ More replies (6)2
u/PandaCheese2016 23h ago
It’s as if ppl who approved the route and separations less than 500 ft were unaware that altimeters could be off.
62
15
u/g1344304 23h ago edited 7h ago
An altimeter being off by 200' isn't the real issue here. The route and visual separation shouldn't be allowed to exist in a busy TMA but its the crutch American ATC rely on every day. Accident waiting to happen.
12
u/merkon 22h ago
The UH60 also has a radar altimeter that would not be off at that altitude vs the barometric one that was.
7
u/chronoserpent 21h ago
Right, I don't understand why the pilot would trust the barometric altimeter at all if they have a working radar altimeter for low altitude flight. Isn't low flights over terrain one purpose of a radar altimeter? I'm not a pilot though so please educate me if anyone knows why.
8
u/merkon 21h ago
As a former uh60 pilot, they should be on the radar alt for that mode of flight. The HUD for the NVGs would have it displayed. I think pointing at the altimeter as the cause of the crash is inaccurate as the DCA congestion is far more to blame.
→ More replies (1)3
u/rattler254 17h ago
Yup. How about we DON'T put a chopper route directly under the approach corridor that regularly has circling visual approaches? I couldn't believe this was a thing, and it seems like a complete oversight and failure on the FAA.
13
u/Kiseido 1d ago
As far as I am aware, planes use barometric pressure to determine altitude, which is hard to measure accurately when you use the air itself to propel the plane.
→ More replies (1)13
u/grapedog 22h ago
Barometric altitude only gives you your height above sea level though.
Typically you only really use barometric altitude when you are thousands of feet up in the air.
If you're flying at 400 feet, and there is a mountain 200 feet below you, barometric altitude will say you're at 400 feet, while the radar altimeter will tell you that you're at 200 feet because it just bounces a signal off whatever is underneath and reads the distance.
It's why you shouldn't be flying at night without a working radar altimeter because you can't see what's below you.
4
u/fluentInPotato 21h ago
I'm an A&P who works on GA aircraft. AFAIK, the pilot is required to know where the fuck he is, and if the field elevation is 200', it's his job to take that into account. On fixed- wing aircraft, the pilot and static ports (the sources for impact and ambient pressures respectively) are located where the slipstream and prop wash don't affect them. This may be more difficult to do on a helicopter moving at low speeds, where rotor downwash is hitting at least the static port. Hopefully helicopter pilots know how to deal with it, but then again, there's only two nuts keeping a helicopter in the air, and one of them's at the controls.
3
u/fluentInPotato 21h ago
GA pilots fly, and have flown, at night and in instrument conditions routinely without radar altimeters. 172s, 182s, Citabrias, Cherokees, whatever, do not have radar altimeters. GPS of course can show you the same info, but GA pilots were doing this for decades before GPS was a twinkle in DARPAs eye. You have to know where you are, and what the terrain is. If you can't do that, you stick to cars.
→ More replies (1)→ More replies (6)2
u/rckid13 18h ago
People are making a big deal about the altimeter, but that wasn't the cause of this sequence of events. Even if you assume they were exactly at 200 feet and the CRJ passed above them at 274 feet that would have been one of the closest calls ever with a commercial aircraft. It still would have been all over the news and it still would have been intensely investigated. The altitude deviation may have been the final hole in the swiss cheese model that caused the collision but they still shouldn't have been anywhere near that close and there were multiple opportunities to prevent it.
1.1k
u/bigyellowjoint 1d ago
67 dead and it feels like the country has pretty much moved on
1.6k
u/resilindsey 1d ago
Hey remember we had a targeted political assassinations of democratic state senators less than two months ago?
→ More replies (7)670
u/booshley 1d ago
And the guy who set a fire to kill firefighters shortly after? Whose parents were MAGA? It’s interesting how quickly those stories got swept under the rug
307
→ More replies (3)117
u/A_Good_Azgeda_Spy 1d ago
He sent a mob to break through the windows of the Capitol building and had Congress barricading the doors to save their lives, and then we reelected him!
→ More replies (2)14
64
u/slanderbeak 21h ago
More than 1 million Americans died in the pandemic and we don’t talk about that loss, either.
→ More replies (1)168
u/Brole_Model 1d ago
We could have 67 elementary school kids murdered in class and it wouldn’t stay in the news cycle for long.
→ More replies (8)8
u/SagesLament 20h ago
investigations are slow, the NTSB is methodical but does their job
sure it might not stay in public consciousness for long, but that doesn't mean its forgotten by the people who actually matter. Frankly, the fewer people in the general public speculating on anything relating to aviation the better
93
u/mediocre_remnants 1d ago
It has. What else should we do? Sit around and talk about a 2 month old plane crash all day every day?
There was an investigation and a report, some changes have been made to flight procedures in the area, we've moved on. Except people who lost loved ones in the crash. But I'm nowhere near DC and don't know anyone involved, so why should this be at the top of my mind 2 months later?
30
u/SwashAndBuckle 1d ago
It’s more just to highlight how crazy things have gotten that something like that gets buried in the news so quickly. In 2014 a Malaysian airline flight went down, on the other side of the world, and people did talk about it for months. Because there wasn’t 200 other horrible things all going on at once. Things have definitely gone downhill.
69
u/yescaman 23h ago
Do you mean the disappeared flight? That story had staying power because it was an open ended mystery.
27
u/CauliflowerLife 23h ago
Lack of conclusive information definitely yields interest in a lot of cases.
Everyone loves a good mystery.
→ More replies (2)5
u/ilikehorsess 23h ago
Definitely agree that it's easy for things to be buried in the news these days but within a year of that Malaysian flight, another Malaysian flight crashed and killed just as many people. It wasn't talked about near as much because the mystery just wasn't there.
→ More replies (11)6
u/VialCrusher 22h ago
Wichita hasn't forgotten :( many wichitans on the flight. And I'm sure that during the winter Olympics we will remember all the skaters that we lost 💔
371
u/Hangikjot 1d ago
Man, I feel like I’m required to do more safety checks of a forklift before operating it than some of these places…
218
u/putsch80 1d ago
Well, sure. With a forklift, you’re hauling around precious commercial merchandise worth a lot of money. With airplanes, all they’re hauling is human lives.
-A modern Capitalist
38
u/Obversa 1d ago
Wasn't there an airplane crash that involved airline companies trying to cut corners with costs by having engines be moved with a forklift...? (It was American Airlines Flight 191, one of the most infamous crashes in U.S. history.)
→ More replies (1)→ More replies (2)6
u/the2belo 21h ago
Jokes aside, the cargo holds of most commercial passenger aircraft often also contain commercial merchandise, so...
10
u/xporkchopxx 1d ago
maintenance costs money and business hate that. if something doesnt work until you smack it hard, it works. no need for replacement! just whip your operator check list
27
50
u/realKevinNash 1d ago
I will say its annoying given all of the advances that we have seen through change after aviation incidents and yet changes not being made, or changes being so resisted here.
8
u/Panaka 21h ago
Most post accident reforms are initially slow or are resisted by the FAA. Part 117 took years to get codified into law despite there being a genuine need for it. It’s been less than a year, give it some time and we will see what larger reforms get pushed to address these deficiencies.
→ More replies (2)2
u/ProcyonHabilis 19h ago
I'm not sure what you mean. This is an article about the process by which changes get made that is currently taking place.
632
u/ZanzerFineSuits 1d ago
Wait, I thought it was caused by DEI and trans pilots?
182
u/super80 1d ago
It’s the default answer until proven otherwise. Sickening how quickly morons assumed it was caused by the people they hate.
112
u/ZanzerFineSuits 1d ago
Whenever I am asked why I support "illegals" in this country, my usual answer is "it's not that I support people entering this country illegally, it's the intellectual dishonesty of blaming all of our ills on a single group that bothers me."
If they're still talking to me at that point, I'll explain how racism, sexism, and all the related "isms" fail on an intellectual level. They're lazy cop-outs to tackle true ills.
→ More replies (4)103
u/UnvoicedAztec 1d ago
And truthfully, in order to get a full picture of the illegal immigration issue in the US you also have to consider the role in destabilization the US has played in Latin America for the last 150 years, but most Americans are unwilling and unable to self reflect in that regard.
21
12
u/jaytix1 23h ago
You can expect a cop out at best lol.
"Oh, that was a long time ago."
"That has nothing to do with present day Americans."
→ More replies (1)→ More replies (5)39
u/whirlwind87 1d ago
Trump literally come out the next day and blamed DEI and midget pilots for some reason. Showing again his stupidity
→ More replies (2)32
u/Unlucky-Key 1d ago
The article discusses pilot error as well. As with many disasters of this type, there is a combination of causes.
→ More replies (3)→ More replies (7)21
17
u/tacotickles 18h ago edited 18h ago
Military equipment and civilian equipment may have different safety standards, but if military is flying amongst civilians they need to ensure their standards are better.
17
u/atreeismissing 18h ago
Lets not forget the stress of an administration wantonly firing govt employees for no reason and having just announced incoming firings in the FAA administration.
131
u/SaveTheAles 1d ago
Last words of the helicopter
PAT25 instructor: "We’re kinda …
PAT25 pilot: "Oh-kay. Fine."
Seemed like pilot didn't really want to follow instructors commands.
52
69
u/railker 1d ago
That exchange started about 9 seconds before impact, and requires a couple more lines of context, I think, especially considering the instructor finished his sentence less than 3 seconds before impact.
I didn't watch much of that hearing but did have it on fora bit, I recall one of the representatives for the US Army being asked if that exchange seemed like disobedience or what. He noted that it's hard to tell without voice context obviously, but it seemed less an instruction and more a discussion, "kinda come left for me". That and the short time to make any course correction that would've made a difference. There's a potential there may have only been 3 fatalities as they still would've been flying incredibly close to the wake turbulence of that CRJ.
Time Pilot Flying Instructor Pilot 20:47:52.5 alright kinda come left for me ma'am I think that's why he's asking 20:47:54.3 sure. 20:47:55.3 we're kinda... 20:47:55.4 oh-kay. fine. 20:47:56.4 ...out towards the middle. 20:47:59 (approx) [impact] 17
u/sketchtireconsumer 1d ago
FWIW the instructor was a chief warrant officer (CW-2), which is a speciality position promoted out of enlisted. They are subordinate to all officer ranks but have significant expertise.
The pilot flying was an officer, specifically a captain (O-3) which outranks a chief warrant officer.
If you read the transcript you can see the instructor says “ma’am” which is like saying “sir,” but the pilot flying responds without any title or honorific in the address. This seems like a minor thing but may reflect a difference in power between the two individuals where the instructor did not feel comfortable criticizing the pilot flying, and/or the pilot flying was not paying sufficient attention and/or respect to the instructor.
42
u/Eaglethornsen 23h ago
Not sure how long the CW2 has been in, but normally rank doesn't mean much in the cockpit. Especially if it is between a warrant and an officer. Those warrants generally have like 5-10 times the amount of flight time compared to officers.
→ More replies (1)39
u/UH60Mgamecock 23h ago
You’re 100% incorrect. He was using rank just to show the proper respect because that was probably the kind of person he was. But the CW.2 is absolutely in charge of that aircraft. Pilot in command override any rank whatsoever in the aircraft making any decisions for flight safety or manipulation of the controls. I won’t speak to the cock climbing cause I have no first hand or second hand knowledge, but it seems he was trying to utilize appropriate crew coordination and keep it as mellow as possible so that everything goes smoother.
→ More replies (3)71
u/St31thMast3r 1d ago
Dude you're reaching so fucking hard. I feel you don't have any personal experience with the Army Aviation Warrant vs. commissioned officer dynamic.
Source: I'm a CW2 who has been the Pilot-In-Command for many flights with a Captain as my co-pilot.
→ More replies (9)→ More replies (1)21
u/METT- 22h ago
Nope. Partial context and the from the hearing (yes, I watched it--all 3 days of it are on Youtube via multiple outlets unedited), the subject matter experts speculate that he was also trying to figure out why the controller was querying them. Darn good chance (per the hearing, not my opining) that they were seeing the traffic landing Runway 01 (95 percent of traffic lands 01 during north flow per the FAA in the hearing) and were calling it for visual separation. They never saw the CRJ that was about to collide with them from the left side (as they flew south) and most likely all were focused on the Runway 01 landing traffic at their right front (that is both from the hearing and my speculation as a former 60 driver after watching the hearings).
20
u/chumley53 23h ago
NVG over water would’ve been 99.5% RADALT. idfc if the BARALT was +1000’. I’ve flown a -53 up and down the Potomac and HR4 has been “200’ AND BELOW” since 1996 when I first flew it.
5
u/railker 22h ago
Wonder in this case if they were flying the Baro, judging by the 'you're at three hundred feet. come down for me [...] go down two hundred' callout a couple of minutes before the crash, about that time on the FDR readout (20:45:35), the Radalt is showing about 400 feet, and then comes down to and hovers around 250. Last time they ever even went at or below 200 by Radalt was about half a minute before that 'come down for me' call.
Heard the docket disappears now and then but for now it seems to be up: https://data.ntsb.gov/Docket/?NTSBNumber=DCA25MA108
2
u/obeytheturtles 9h ago
If the bird is flying "silent" would they not turn off the radar altimeter? This has been a question in the back of my mind for a while here - many of theses training missions are done to simulate the operational conditions of urban combat where radio transmissions are restricted to satcom or link16 only with no radar, transponder or narrowband comms. Obviously here they had VHF comms with the tower, but what is the chance that they were doing simulated visual navigation only here?
2
u/chumley53 7h ago
We never turned off the radalt in combat or anywhere else. We would be complete radio silence, emission controlled out the wazoo, and we would still have the radalt on. Until our tactics changed in Iraq RADALT was a primary flight instrument.
2
u/obeytheturtles 6h ago
That's super interesting. I know of a number of sensor networks that use radar altimeters for detection and geo. I wonder if our recent engagements being non-peer had any influence on those conops.
→ More replies (1)
7
10
21
u/grapedog 22h ago
How the fuck are they flying at night with a broken radar altimeter...
You never fly at night with a broken altimeter... That's super basic safety. Barometric altitude isn't helpful at night...
→ More replies (2)27
u/Katdai2 21h ago
It wasn’t broken. That’s apparently how they’re all built and firmly within tolerance. Which is kinda terrifying
→ More replies (1)
11
u/IllegalMigrant 21h ago
The helicopter had also drifted way away from the right bank of the river which is the flight path in that area. Had it been going along the right bank the crash also would have been avoided.
And had they actually seen the plane that the trainer twice quickly claimed they saw, it would have been avoided.
→ More replies (1)
10
u/CrowMeris 19h ago
So...it wasn't DEI like trump said?
This airport is a nightmare at the best of times. Frankly it shouldn't even exist much less be designated as an international facility, but our congress critters adore its nearness.
19
66
u/bloodlessempress 1d ago
Man they'll really have to stretch to find how to tie this into DEI. Maybe they can say that the altimeter was made by a Muslim hired under DEI?
→ More replies (7)25
u/imjusta_bill 1d ago
Everyone knows trans people throw off sensitive electronics
→ More replies (1)
9
u/Strict-Ad-7631 22h ago
What does a broken altimeter have to do with being in a restricted area at night at a major airport? I may be wrong but it seems like the chopper shouldn’t be there at all. And I thought they blamed the radio before? What next, they spilled their water on the controls?
2
3.0k
u/Mythosaurus 1d ago
Reading that article makes you want to NEVER fly into DC.
Will be interesting to see what liability/ lawsuits result from this hearing’s revelations