Something going on around DC

[Kenny Phillips]

CBS says "An unresponsive airplane flying over Washington, D.C., on Sunday prompted military fighter jets to intercept the plane at hypersonic levels ..."
I get the new jets are a bit faster than I thought.
Sounds like another Payne Stewart thing. Four dead.

 

[DaleB]

Assuming the plane is in ALT Hold mode with zero thrust, the AP is going to pitch the plane up into a stall. I do not think this model has anything that would disconnect the AP with stall warning. It does have over-torque disconnect.

Really? Even the older low-end AP in my cheap little RV-12 won't try to hold altitude into a stall. It's got a minimum airspeed (and a max) that will limit climb/descend/alt hold.

 

[2-Bit Speed]

Hmmm..... Wonder what the media is going to do with this one.

The contrails are turning the friggin' frogs gay!!

 

[EdFred]

I think it’s a coincidence that the last heading in the flight plan had it heading back in the direction of the departure airport.

I saw that too. Unless the autopilot just loops the flight plan if waypoints from it aren't deleted. The heading does change after CCC --> ISP (only a couple degrees) so maybe it was flying back to 0A9 because wouldn't HDG mode keep it flying at exactly nnnº ? the heading did change from 240º to 236º would take into account the difference between 12W near ISP and 8W variation near departure.

 

[Rcmutz]

“the heading did change from 240º to 236º would take into account the difference between 12W near ISP and 8W variation near departure.”

Boy, somebody didn’t have much to do yesterday! East is least, West is best!

 

[catmandu]

Boy, somebody didn’t have much to do yesterday!

Honestly, I deserve that light hearted poke as well: Direct 0A9 would follow a great circle route which would have been an even bigger change in heading/track (ten degrees I think Foreflight told me yesterday), so my conclusion was runway heading/track hold after last waypoint.

 

[John Spartan]

Just curious. There were 53 minutes from the NYC turn to impact with the ground. Is that not in the reserves? Hard to believe they would stay at 34,000 feet and not land when less than an hour of fuel remained.

 

[Dave Theisen]

After ISP the autopilot wouldn’t have any Nav source to follow and would just go into roll mode and keep the wings level.

 

[EdFred]

Just curious. There were 53 minutes from the NYC turn to impact with the ground. Is that not in the reserves? Hard to believe they would stay at 34,000 feet and not land when less than an hour of fuel remained.

Was filed for 39000. Would have used less fuel at 39000 and also less fuel while descending at reduced power. Also 45 minutes is the reserve while IFR.

 

[EdFred]

After ISP the autopilot wouldn’t have any Nav source to follow and would just go into roll mode and keep the wings level.

I would think it depends on the GPS / AP combo. We have seen in the past where a plane kept flying to the last waypoint and kept flying racetrack after racetrack until fuel exhausting.

 

[CaptainDoug]

Let’s say pilot is incapacitated. Auto pilot flying the plane. What could account for it hangin’ a 180 over destination and then just flying straight ahead, looking like back to departure point

I believe that it was just a coincidence that the plane flew back to the direction of the departure point.

The autopilot flew the flight plan that was already put into the FMS (Flight Management System) and then when it got
to the destination it just flew the course that it was already on to get to the airport. It's just a coincidence that
the course was in the same direction as the departure airport.

This sounds like hypoxia to me - either due to a gradual or sudden decompression.

I also think that some pilots can get too complacent - the fly for years and never
experience any loss of cabin altitude. And then, when it happens, they don't get
the oxygen mask on soon enough. Maybe it's a gradual decompression and they
feel giddy (semi-euphoric) because they're getting hypoxic? I've read that it
could be like being drugged - you feel like there's nothing wrong in the world.
But you're losing oxygen to the brain. And then it's too late once you pass out.

 

[jkgoblue]

So at what point did this plane lose radio contact with ATC? Does anyone have any ATC recordings with the plane before it went silent? I mean did they lose contact before it got to Islip? If so, don't you think it would have generated some concern way before it got over DC? I'm not following...

 

[Flying Keys]

Honestly, I deserve that light hearted poke as well: Direct 0A9 would follow a great circle route which would have been an even bigger change in heading/track (ten degrees I think Foreflight told me yesterday), so my conclusion was runway heading/track hold after last waypoint.

It was coincidental. Here's the overlay of the flown path (mostly in red) and the direct, great-circle line from 0A9 to ISP in yellow. As we can see, the flown path was diverging, as the AP probably went into ROL (wings-level) of HDG mode after the last waypoint, depending on the AP model. Either would be subject to wind drift as well.

 

[CaptainDoug]

Have flown several citations in the past. Some types have “EDM” (emergency descent mode). If the AP is engaged above FL310, and there is a rapid decompression, the airplane will automatically turn and descend without crew assistance.
Not saying that’s what happened here.

That's true on the newer Citations. I think that this particular Citation V was 33 years old. The FAA records show that it was built in 1990.

Also, in the EDM (emergency descent mode that's done by the autopilot) the airplane
needs to be above FL300 and the cabin altitude above 14,500. I believe that
this Citation V was just at FL340 - so I don't think that it had EDM.

 

[Pinecone]

They went to guns, two shots, one for each tank (and don’t be f’ng up my punchline with how many tanks are in each wing)

Uuuh, the Vulcan in the F-16 fires 6000 rounds per minute. There is no single round option. You cannot manipulate the trigger to only fire one round at a time.

 

[Pinecone]

I can picture one engine flaming out and with service ceiling on one engine being mid twenties it starts a descent that the autopilot tries to keep up with. Soon it begins the turn, then when second engine fails the autopilot definitely can’t keep up. Then AP disconnects.

It depends on how smart the AP is. Lose an engine with altitude hold, and it tries to hold altitude until the plane stalls. APs can do this if you set a climb with a set vertical speed, but the aircraft cannot maintain that vertical speed any longer, the AP keeps pitching up trying to do it.

 

[luvflyin]

Uuuh, the Vulcan in the F-16 fires 6000 rounds per minute. There is no single round option. You cannot manipulate the trigger to only fire one round at a time.

I want to just let this go. Wish I hadn’t made that post.

 

[IK04]

The TV talking heads were actually using the word "hypoxia" after the tapes from the intercept stated the pilot was unresponsive.

 

[Kenny Phillips]

Uuuh, the Vulcan in the F-16 fires 6000 rounds per minute. There is no single round option. You cannot manipulate the trigger to only fire one round at a time.

But you can choose a three-round burst.

 

[Mongoose Aviator]

Even the older low-end AP in my cheap little RV-12 won't try to hold altitude into a stall.

I never even thought about trying that with my ancient APs. Next time I am up doing stall practice, I will give the AP a try into a stall and see what it does.

 

[Mongoose Aviator]

I want to just let this go. Wish I hadn’t made that post.

Just apologize and note that you are deleting it. Then ask people who quoted you to also delete it. Perhaps they cooperate.

I post stupid stuff all the time. After I realize it was stupid, I (sometimes) apologize then delete it. Anybody who posts on any type of social media knows how that goes.

 

[John Spartan]

Was filed for 39000. Would have used less fuel at 39000 and also less fuel while descending at reduced power. Also 45 minutes is the reserve while IFR.

Ok. So after the NYC turn they flew 8 minutes then we’re in their reserves? It was about 53 minutes from that turn to no more signal. For signal to disappear at 29,000 feet going about 440 knots, seems like in flight break up had to happen. The real question is if they had help “breaking up” from an F16 since they had already passed over DC and were headed towards VA where the Pentagon and CIA Langley are located. My confidence in our government is low enough to be suspicious at this point. Jus saying.

 

[geezer]

Since the ATC was obviously having communications problem with an unresponsive crew at least from the time a normal descent into Islip should have started, why was the response with jet fighters so late?

That should have been discussed as a possible need at the time of the course reversal at cruise altitude. A fighter from Maguire AFB in NJ if they have them, would have made sense. Such deployments have been done many times to verify pilot incapacitation. That should have been well established before near Washington FRZ, and a scramble for a supersonic chase completely unnecessary.

Once the Citation was traveling away from the FRZ, anywhere it went down was better than inside the beltway, so let it go.

The lack of smoke at the hole in the ground supports the fuel exhaustion assumption.

My household did hear the boom. I feel safer, knowing the F16 did catch up before the crash........

Sad to have them die, but if pressure loss, gentle process, and gone well before the actual crash.

 

[Doc Holliday]

Ok. So after the NYC turn they flew 8 minutes then we’re in their reserves? It was about 53 minutes from that turn to no more signal.

In fuel planning on a jet, the last hour takes into account the descent and approach, which will be lower FF than at cruise. IFR reserves are 45 minutes.

Depending on the jet, most operators have a min lbs number to land with giving area, weather and known delays.

 

[IK04]

There were several videos of people reacting to the boom(s). Some of those folks looked like they were experiencing the end of the world and freaked out.

Being a child of the '50s-'60s, I would have recognized it immediately...

 

[brcase]

I believe that it was just a coincidence that the plane flew back to the direction of the departure point.

The autopilot flew the flight plan that was already put into the FMS (Flight Management System) and then when it got
to the destination it just flew the course that it was already on to get to the airport. It's just a coincidence that
the course was in the same direction as the departure airport.

This sounds like hypoxia to me - either due to a gradual or sudden decompression.

I also think that some pilots can get too complacent - the fly for years and never
experience any loss of cabin altitude. And then, when it happens, they don't get
the oxygen mask on soon enough. Maybe it's a gradual decompression and they
feel giddy (semi-euphoric) because they're getting hypoxic? I've read that it
could be like being drugged - you feel like there's nothing wrong in the world.
But you're losing oxygen to the brain. And then it's too late once you pass out.

I was fortunate enough be able to take an altitude chamber course a number of years ago.
I wish these were more available for civilians.

They showed us the following video as part of that course...

What stands out to me is the "Sir, you are going to die, put on your mask!!" (paraphrased I am sure), and his response is "4 of spades"

I think this brain going into a loop is a fairly common exterior symptom of hypoxia, the dangerous part is the victim (??) doesn't even realize they are doing it.

I am aware of another accident last year where an experienced pilot encountered a hypoxia event (mechanical issue) and continued on a course a line (fortunately he was in a slow descent) until he was at a location that he had no other option but to ditch the aircraft.
Afterwards he remembered doing it, but was at a total loss to explain why he did it, it wasn't until a couple months after the accident the likely issue with the O2 system was discovered.

Brian
CFIIG

 

[Randomskylane]

But you can choose a three-round burst.

Seems likely that they have more sophisticated methods these days (back door override of avionics for example)

 

[dbahn]

Apparently there were three passengers on board. I wonder if any of them ever knew what was going on or if they just became quietly hypoxic and slept through the nightmare.

 

[Rich Holt]

I was fortunate enough be able to take an altitude chamber course a number of years ago.
I wish these were more available for civilians.

They showed us the following video as part of that course...

What stands out to me is the "Sir, you are going to die, put on your mask!!" (paraphrased I am sure), and his response is "4 of spades"

I think this brain going into a loop is a fairly common exterior symptom of hypoxia, the dangerous part is the victim (??) doesn't even realize they are doing it.

I am aware of another accident last year where an experienced pilot encountered a hypoxia event (mechanical issue) and continued on a course a line (fortunately he was in a slow descent) until he was at a location that he had no other option but to ditch the aircraft.
Afterwards he remembered doing it, but was at a total loss to explain why he did it, it wasn't until a couple months after the accident the likely issue with the O2 system was discovered.

Brian
CFIIG

There is a new-ish device where you wear an oxygen mask while on a flight simulator and they mess with the O2 percentage at random intervals. It is a much more realistic demonstration of the slow onset of hypoxia. The USN had just started using the partial pressure trainer when I tapped out in 18. The chamber is a little bogus because you know it is about to happen and you can see other people putting their masks back on. Yet people still fail on a pretty regular basis requiring re-rides...

 

[Jeff767]

But you can choose a three-round burst.

You can select 4000 or 6000 rounds per minute. There is no 3 shot burst.

 

[MauleSkinner]

I was fortunate enough be able to take an altitude chamber course a number of years ago.
I wish these were more available for civilians.

I don’t think increased availability would have a huge effect…one place I worked, a training provider “gave” us altitude chamber course slots for all 21 pilots. 2 of us actually used them.

 

[Flying Keys]

Ok. So after the NYC turn they flew 8 minutes then we’re in their reserves? It was about 53 minutes from that turn to no more signal. For signal to disappear at 29,000 feet going about 440 knots, seems like in flight break up had to happen. The real question is if they had help “breaking up” from an F16 since they had already passed over DC and were headed towards VA where the Pentagon and CIA Langley are located. My confidence in our government is low enough to be suspicious at this point. Jus saying.

Unfortunately your confidence in the gov’t is lower than your confidence in your geography.

 

[Flying Keys]

In fuel planning on a jet, the last hour takes into account the descent and approach, which will be lower FF than at cruise. IFR reserves are 45 minutes.

Depending on the jet, most operators have a min lbs number to land with giving area, weather and known delays.

This. And who knows if they even made it to their filed cruise altitude and planned cruise power setting.

 

[TCABM]

…My confidence in our government is low enough to be suspicious at this point. Jus saying.

Submit an FOIA request for the DEN recording. It’ll probably take a while since NTSB is likely going to sequester it until the investigation is complete. You can also FOIA EADS for records and recording relating to the incident. That will likely also be a long time coming due to the investigation, but all .mil communications between the fighters and EADS will have been recorded and there will be written logs for the entire event.

 

[FPK1]

CNN reporting -

Four first responders who arrived at the scene of Sunday’s fatal private plane crash near Raphine, Virginia, told CNN the plane left a “crater,” and they believe it impacted the ground at a very steep angle.

The first responders, who spoke on the condition they not be identified, described a grisly scene. There were perhaps four recognizable pieces of wreckage from the plane, they said. “There was nothing really bigger than your arm,” said one.

They also found signs of human remains.

https://www.cnn.com/2023/06/05/us/virginia-plane-crash-fighter-jets-investigation-monday/index.html

 

[EdFred]

Ok. So after the NYC turn they flew 8 minutes then we’re in their reserves? It was about 53 minutes from that turn to no more signal. For signal to disappear at 29,000 feet going about 440 knots, seems like in flight break up had to happen. The real question is if they had help “breaking up” from an F16 since they had already passed over DC and were headed towards VA where the Pentagon and CIA Langley are located. My confidence in our government is low enough to be suspicious at this point. Jus saying.

No they would have had more reserved due to less fuel used at a higher altitude and reduced power settings for descent.

 

[Zeldman]

There were several videos of people reacting to the boom(s). Some of those folks looked like they were experiencing the end of the world and freaked out.

Being a child of the '50s-'60s, I would have recognized it immediately...

Same here. As a kid sonic booms were not heard everyday, but were definitely a lot more common in summer.

The last sonic boom I heard was in Florida in 1993 as the space shuttle came over head for landing at Cape Canaveral, at 5:30am....

 

[MPB]

As a LSU person it's interesting to note that this ghost plane stuff started in 1980 with the Conquest with LSU's football coach on it - way back time but I don't really recall any accidents of this type prior to that.

Some pretty spectacular ones since then Payne Stewart, TBM owner association head, etc. Sure seems these are getting more common, although likely a function of increased flight level GA activity likely low hanging fruit in terms of safety improvement.

 

[Kenny Phillips]

There were several videos of people reacting to the boom(s). Some of those folks looked like they were experiencing the end of the world and freaked out.

Being a child of the '50s-'60s, I would have recognized it immediately...

I was thinking exactly that. We heard them all the time, looked for the planes, until enough people complained.

 

[John Spartan]

Fe

Unfortunately your confidence in the gov’t is lower than your confidence in your geography.

Yes, lord help us for missing something in geography. But we have YOU here to contribute… exactly what? Ah. Nothing. You’re lacking commentary aside, our government routinely screws up these days. I find there is more to question about our leadership than there is to trust. In this case, there are plenty of questions and what are turning out to be convenient coincidences. Feel free to trust the government all you like. But seriously. Thanks for that stellar comment.