Posts about: "Blackhawk (H-60)" [Posts: 170 Page: 5 of 9]¶

The issue here, I believe, is that there's different standards for visual separation vs radar separation. A separation that results in a CA from the radar may still be entirely legal and acceptable. It's like trying to work out if two cars at an intersection will crash into each other from their GPS trackers: the data just isn't good enough and you don't know if one car will actually stop at the stop sign at the last second.

Radar orders also need to be given and actions taken sooner than if the crews are doing it of their own initiative. So a radar CA needs to be visible say 15 second pre-collision so ATC can wait for the radio to be clear then order pilots to manoeuvre. Pilots can aim to cross visually at more like 5 seconds.

I'm not saying that this is overall a good idea, but the fundamental reason you fit more planes in with visual separation is that you can put them closer together with (given good visibility) not too dissimilar safety.

[Edit: too late... Fullwings got this.]

One aircraft gets a PULL UP, the other gets a NO CLIMB. Ideally you would have each aircraft advertise how much altitude it can gain/lose in 5/10/15 seconds and make the decision based on that. It would also fix needing to turn to TA only after engine failure.

To the contrary, you're legally obliged to..


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G/S was >100kts

R-22 v UH-60L/MH-60 etc.. yes they are absolutely different, have different paint n everything, different spelling and all. The relationship of inertial vs aerodynamic forces on the rotor system. generally referred to as the Lock number are worlds apart. It may seem like a meaningless number but it is what gives the characteristics of the harmonic control that you, the rotary pilot are actually controlling. It also uses similar factors that determine the tip path plane of the rotor for different conditions and the relationship between control input, swash plate plane and the tip path plane of the rotor.

During a quick stop, your instructor was correct to prepare you for what follows rapidly thereafter with respect to your heading and your need to be ready for some footwork, and to be aware of the torque demand that follows where the wake influences your aircraft. This isn't however vortex ring state, nor is it settling with power, it is a transient related to your wake. The R-22 has adequate but not fantastic tail rotor authority, the UH-60 has an excellent tail rotor befitting a damned fine tactical/combat helicopter.

You can get through a complete aviation career in helicopters without opening up any books beyond your training manuals. Helicopters also bite back hard if you.step out of line, so my suggestion is that you may frame Torquetalk's comment: “you don’t know what you don’t know” , and enjoy reading about your machines physics.

How does a Blackhawk pilot bust airspace by about 125ft?
Wouldn't they have their arse handed to them?

60 knots, but slowing down would not be a bad idea. The SH-60 and UH-60 fly smoother at 60 than 50 IME, due in part to how and when the horizontal stab changes pitch based on the FBW set up for that flight control surface.
Their penalty was a bit more severe than that: they died, and sadly took a bunch of other people with them. I also am puzzled at the delta between their altitude requirement on that route and the altitude at impact. As John Dixson had noted, UH-60's have a rad alt.
So it wasn't just me.

I don't think it make a significant turn right, and I believe that what you are seeing is positional inaccuracy due to MLAT position limitations in the ADS-B Exchange data. According to Flightradar24, " MLAT position calculations have a general accuracy of 10-100 meters and 1000 meters in the worst cases." Given that, I believe this previous post from MikeSnow AA5342 Down DCA represents our best current understanding of the actual helicopter track and its relation to Route 4 (until we get more information from the NTSB). I generated my own zoomed overlay and got essentially the same results



The position of the collision shown in the radar data overlay is consistent with the position of the RJ as shown in ADS-B Exchange at the time of the collision (approximately 01:47:59Z according to the NTSB timeline). See this link from DIBO for the RJ Track with timing AA5342 Down DCA In my experience, times in ADS-B Exchange are generally accurate to within 2 seconds. Given all that, I believe that the Black Hawk was within the horizontal bounds of Route 4 at the time of the collision and that it did not make the right turn we see in the ADS-B Exchange map.

Edit: Corrected route number and helicopter

Had there been a fourth crew member in the Blackhawk, which routinely would have been seated on the port side with a view in the direction the CRJ was approaching the helicopter....you reckon there might have been a possibility that might have allowed for the sighting of the CRJ and thus prevent the collision?

Owing to the vision limitations caused by use of NVG's it is not out of the realm of consideration Army policy would require for two crew members in the rear of the aircraft to enhance conflict resolution.

We routinely flew Chinooks with three crew in the rear with two designated to watch for traffic on either side of the aircraft. The third crew member was the Flight Engineer who controlled activities in the rear and performed safety checks. That simple concept saved my Bacon more than a few times.

NYT has attempted a reconstruction of the visual picture from the Blackhawk at the time of the first traffic alert, with the CRJ just south of Wilson Bridge.
They could only later identify the correct light spot by following its trajectory according to their mental image of the approach to 33.

The original NYT article thanks to the Internet Archive (archive.org) .

Yes, but their ATC transponder was obviously operating normally in C mode. That should be enough to show PAT25 on CRJ screen as traffic, even if no RA was given (bearing in mind, they were cca 300ft AGL) It is of course completelly unreasonable to expect that CRJ crew should see or even avoid the Blackhawk incoming from (slightly) right, as they were merely 20-ish seconds from touchdown and manually aligning with the runway. Also, I believe that operating ATC transponder on Blackhawk allowed for clear view on ATC screen and I wonder if there was no alarm triggered on ATC computers - they probably do have such guard software in operation on DCA?
In another midair collision report, that happened in July 2022 at NorthLas Vegas airport, NTSB put out this:
Interviews with personnel at the air traffic control tower indicated that staffing was deficient, and most staff were required to work mandatory overtime shifts, reaching an annual average of 400 to 500 hours of overtime per controller. According to the air traffic manager (ATM), the inadequate staffing had resulted in reduced training discissions, and the management team was unable to appropriately monitor employee performance. The ATM stated that everyone on the team was exhausted, and that work/life balance was non-existent. It is likely that the cumulative effects of continued deficient staffing, excessive overtime, reduced training, and inadequate recovery time between shifts took a considerable toll on the control tower workforce.
I wonder, how this situation is with DCA ATC service.
I am not trying to blame ATC either. He issued clearance to PAT25 to cross behind and asked (and got) confirmation for CRJ in sight twice. It seems quite clear that helicopter crew did not look at the same airplane that ATC was asking about.
What baffles me here is, that it was obvious a routine procedure to let helicopters cross active runway heading less than 2 miles from runway treshold, leaving practically zero margin for error. Backups, designed to catch pilots or ATC errors (TCAS and ATC alarms) cannot catch up in short time left if someone makes a mistake, so this arrangement as based on "see and avoid" concept, in the night, with many lights in the background and a fact, that other aircraft on collision course does not move relatively on the screen, but just grows bigger. Unfortunatelly, that dot on the screen that will kill you starts growing bigger only in the last few seconds.
If I would ask ATC to cross runway heading DAY VFR so close to runway treshold at my airport with incoming commercial traffic, I would be denied 100 times out of 100 attempts. (and probably called nuts).
My guess on this tragedy is, that thru the years, the system was trying to pack more and more aircraft in the same space and same infrastructure, by gradually squeezing margins and safegueards, until one day, Jenga tower collapsed.

Thanks for the picture. So three possible light blobs very close together AA5307 (short of landing), AA5342 (the CRJ), AA3130 (which was picked by PAl25 as conflict)

Regarding to the Pavlovian - if PAL25 wouldnt have requested 'visual separation', what "punishment" would they expect from the Tower? Orbit(s)? Vectors? Or somethin wild, considering 200/300' altitude limits along the river and buildings/infrastructure left and right (what diameter would an orbit cost with a Blackhawk, is it feasible over black water at 200')? Therefore I am asking - would a non-request of a 'visual separation' mean major complications to such a helicopter at night? That as well would then be a significant flaw in the design.

I believe visual separation from other aircraft is a very different scenario to visual separation from ground obstacles (VFR).

Waiting for the tower to have no aircraft below ~700ft in the approach area, if we're assuming a 1.5Nm separation, could be quite a while.

We don\x92t know if they were looking at the wrong traffic or not, yet. We do know they hit the traffic they said they would pass behind. Might just be a military Blackhawk thing. A thousand lowtime Robbie pilots flying single-pilot are told to pass behind landing traffic routinely and somehow manage to do it. On this thread you\x92ve read that Blackhawks need two crew chiefs in the back to help look out for traffic, and that the pilots are obliged to wear NVG on this route even though they can\x92t see **** with them on in the urban cultural lighting.

Done this myself for 50 years, night, single-pilot, high-density airports, single and multiengine, never had an issue identifying the aircraft tower pointed out to me.

Keep looking.

The Black Hawk crew had lost totally their situational awareness. If you are instructed to pass behind a traffic which is landing on rwy 33 how can you be on final rwy 33 before the traffic has passed you? Perhaps they noticed that they were approaching the final of rwy 33 and started a right hand climbing turn, but too late.
CRJ was possible behind the windsield frames in the first sight but anyway it was not conflicting traffic while it was on the base for rwy 33. Final turn at below 500ft doesn’t make it any easier for the helicopter to realize/react to the changing situation.

One thing came to my mind: was the PAT 25 avoiding the traffic by flying ahead of the CRJ instead behind it in first place? ”Pass behind” was told only 18 seconds before the impact.

+1
I think many pilots would have made a mistake indentifying : seen from the helo, there are 3 aircraft in final, plus 1 on take-off, at the same bearing, how can you tell for sure which is the one "just south of Wilson Bridge" ?

This simulation, if correct, is harrowing. The accident aircraft is actually almost superimposed over the following aircraft AA3130 at exactly the time of the tower's first notification of traffic to the helicopter. The helicopter's response is so quick, so reflexive. Then when the second notification is received, even though PAT25 knows he has just asked for visual separation and been granted he asks again, further suggestion that this is reflexive behavior.

At the same time the accident aircraft peels off to the right to swing around and line up to 33, thus taking his (smaller) lights out of the helicopter's direct line of vision and leaving 3130's (brighter) lights still heading to 01 to decoy the pilot. The reflexive nature of the helicopter's responses suggest to me that the full implication of 'circling to 33' in the tower's first call was missed, and also sort of implies that the helicopter could not conceive that following (nearly) the published heliroute could lead him into conflict with an aircraft on final. Me neither.

I'd push the expiry date of that one out a little.

I think the collision was closer to 1250m (4100') from the PAPI. I base that upon the NTSB statement " At 8:47:58, the crew had a verbal reaction, and FDR (flight data recorder) data showed the airplane beginning to increase its pitch. Sounds of impact were audible about one second later," That puts the collision at about 8:47:59 (01:47:59Z). ADS-B Exchange data at that time puts the ground distance to the PAPI between 1200-1280m (3900-4200'). My assumptions are that the NTSB statement is correct and that the ADS-B Exchange data is accurate (which in my experience, the times are generally less than 0.2 seconds later than the timestamps on data collected by the FAA, and the reported NACp (position accuracy) was estimated at < 10m). Here is the graphical representation I generated of my estimated collision position vs. PAPI.


Collision Altitude vs PAPI

If my depiction is accurate, it's hard to see why they would pitch up as normal input to approach path. I think their inputs would have been focused on getting down.

Long version of Wall Street Journal article about changing DCA airspace use rules, from WSJ website (summary in print edition Feb. 12):
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Federal air-safety officials want to permanently keep helicopters away from commercial jets taking off and landing at a busy Washington, D.C., airport after the deadliest U.S. aviation accident in more than two decades.

The move, under consideration by senior Federal Aviation Administration officials, would be part of a long-term plan to improve safety at Ronald Reagan Washington National Airport, according to people familiar with the discussions.

Helicopters have been temporarily barred from flying in a corridor used by the U.S. Army Black Hawk that collided on Jan. 29 with an American Airlines regional jet, killing 67 people. The chopper routes have been used to ferry senior military officials around the region and to train for a \x93continuity of government\x94 mission in the event American political leaders need rapid evacuation from Washington. Other government agencies have also used the routes.

Federal officials have said they would revisit the helicopter restrictions once the National Transportation Safety Board issues a preliminary report on the accident in the coming weeks. Preliminary indications from the probe point to multiple factors potentially contributing to the crash, including the design of the airspace, as well as actions by the helicopter pilot and air-traffic controller, according to people familiar with the investigation.

The NTSB said it would examine how far apart planes and helicopters are supposed to be while flying in the airspace.

Transportation Secretary Sean Duffy has criticized the Pentagon\x92s operation of helicopters near the airport. \x93If we have generals who are flying in helicopters for convenience through this airspace, that\x92s unacceptable,\x94 he said last week. \x93Get in a damn Suburban and drive. You don\x92t need to take a helicopter.\x94

The Army said it would continue to comply with FAA requirements and restrictions to enhance flight safety. The service said it was reassessing its aircraft operations near the airport and that it gave priority to the safety of the public and military personnel. The current restrictions allow certain critical flights.

Duffy also suggested certain military missions can be done at a different time of night. The Jan. 29 crash occurred around 9 p.m. Eastern time.

Defense officials have assumed that the helicopter routes would be closed in the coming months amid several ongoing investigations, but have privately said that the routes should be reopened. Adjustments under consideration if routes are reopened include limiting hours for training and test missions.

Reagan\x92s convenient location, a few miles from Capitol Hill, has made the nearly 84-year-old airport a favorite among politicians, business executives and tourists.

Space is tight at the airport. Reagan\x92s longest runway, Runway 1, is the nation\x92s busiest, airport officials have said, and it has two smaller runways. Routes into and out of the airport are constrained by no-fly zones around sensitive government buildings.

The FAA has said it is also reviewing airspace around airports aside from Reagan that also have high volumes of helicopter and airplane traffic.

Discussions about Reagan airport have also focused on a small runway known as Runway 33, people familiar with the matter said. The American Airlines regional jet was attempting to land there when it collided with the Army helicopter. Some government and industry aviation officials believe that there isn\x92t a problem with planes using the runway if helicopters aren\x92t near the traffic lanes.

Warning signs existed for years about risks facing commercial passengers, with planes sharing the skies closely with helicopters zipping up and down the Potomac River.

The path the American Airlines regional jet took toward Runway 33 required it to turn toward the right and then bank left to line up for its landing. That route crosses over a lane for helicopters at a relatively low altitude.

There have been at least 35 events involving conflicts between helicopters and flights into and out of the airport that have been flagged since the 1980s, according to a Wall Street Journal analysis of anonymous reports to a system overseen by the National Aeronautics and Space Administration.

In one instance, in July 2018, a helicopter and small plane came within roughly 580 feet of each other while the plane was approaching Runway 33. The helicopter pilot had to maneuver to avoid the plane and questioned the air-traffic controller about it after, according to an internal FAA report on the incident viewed by the Journal.

Neither aircraft had received traffic advisories or safety alerts, the report said. The helicopter pilot reported the incident as a near midair collision. \x93I\x92m sorry for the confusion,\x94 the controller told the helicopter pilot, according to an audio recording of air-traffic-control communications following the incident.

Nearly two weeks after the deadly crash over the Potomac, the FAA has lifted some of the constraints put on Reagan airport in the wake of the accident.

The FAA on Tuesday boosted the airport\x92s arrival rate from 26 to 28 aircraft an hour, after temporarily reducing it to ease the strain on controllers still dealing with the aftermath of the crash, according to an email viewed by the Journal and earlier reported by other news outlets. The current rate is still lower than the airport\x92s typical maximum of 32 arrivals an hour.

Reagan\x92s two smaller runways, which had been closed due to search and recovery efforts, have been reopened.
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Just heard NTSB briefing. It seems that the scapegoat will not be any of the humans involved, nor even the procedures, but the altimeter system of the black hawk (a 100 ft discrepancy) and the radio (they did not hear "circling" and "pass behind")