ATC: PAT25...PASS BEHIND...CRJ7"
NTSB Cleared up the ATC instruction to helicopter PA25
Ipsis Litteris
NTSB Feb. 14, 2025, NTSB Briefing Points on Mid-air
Collision near DCA
Preliminary investigative information which is derived from
a variety of electronic and other sources as of 1:00pm today.
• About 8:15 pm EST, the CRJ left 37,000 feet pressure
altitude for an initial descent.
• About 8:30, the Blackhawk began travelling generally
southbound after maneuvering near Laytonsville, Maryland. CVR audio from the
Blackhawk indicated the instructor pilot was the pilot monitoring and
transmitting on the radio and the pilot was the pilot flying. (ATC Radar &
Blackhawk CVR)
• At 8:33:41, the Blackhawk crew requested Helicopter Route
1 to 4 to Davison Army Air Field, which the tower controller approved.
• 8:38:39, the Blackhawk reached the intersection of the DC
Beltway and the Potomac River near Carderock, Maryland. After briefly turning
westbound, the Blackhawk turned back to the east and began descending as it
picked up helicopter route 1 over the Potomac River southeast toward downtown
Washington, DC.
• At 8:39:10, Potomac Approach cleared the crew of the CRJ
for the Mount Vernon Visual Runway 1 approach.
• At 8:40:46, the CRJ rolled out of a left turn established
on the ILS Localizer for
Runway 1, at approximately 4,000 feet pressure altitude, 170
knots, with
landing gear up and flaps extended to 20 degrees.
• At 8:43:06, the CRJ crew made initial contact with DCA
Tower. The tower
controller then asked if the crew could switch to runway 33.
The CRJ crew
agreed to switch to runway 33.
• At 8:43:48, the Blackhawk was about 1.1 nautical miles
(NM) west of the Key
Bridge. The pilot flying indicated they were at 300 feet.
The instructor pilot
indicated they were at 400 feet. Neither pilot made a
comment discussing an
altitude discrepancy. At this time, we do not know why there
is a discrepancy
between the two; the investigative team is exploring this.
• At 8:44:27, as the Blackhawk approached the Key Bridge,
the instructor pilot
indicated the Blackhawk was at 300 feet descending to 200
feet.
• Between 8:44:41 and 8:44:45 the CRJ crew selected 30
degrees of flaps and
then 45 degrees of flaps.
• At 8:44:49, the CRJ landing gear were down and locked. The
aircraft was fully
configured for landing, approximately 6.2 NM south of the
airport.
• At 8:45:27, the autopilot was disconnected and the CRJ
began a shallow right
turn off of the Runway 1 localizer at a radio altitude of
approximately 1,700 ft
and an airspeed of 134 kts. This occurred approximately 5.0
NM south of the
airport.
• At 8:45:30, the Blackhawk passed over the Memorial Bridge.
The instructor
pilot told the pilot flying that they were at 300 feet and
needed to descend.
The pilot flying said they would descend to 200 feet.
• At 8:45:58, the Blackhawk then crossed over the Washington
Tidal Basin and
followed the Washington Channel consistent with Helicopter
Route 1.
• It is now approximately two minutes before the collision.
• At 8:46:01, a radio transmission from the tower was
audible on the CRJ CVR
informing the Blackhawk that traffic just south of the
Wilson Bridge was a CRJ
at 1200 feet circling to runway 33.
3Feb. 14, 2025, NTSB Briefing Points on Mid-air Collision
near DCA
• CVR data from the Blackhawk indicated that the portion of
the transmission
stating the CRJ was “circling” may not have been received by
the Blackhawk
crew. We hear the word “circling” in ATC communications, but
we do not hear
the word “circling on the CVR of the Blackhawk. The
Recorders Group is
evaluating this.
• At 8:46:08, the Blackhawk crew responded they had the
traffic in sight and
requested visual separation which was approved by DCA Tower.
• At 8:46:29, the CRJ crew received a 1000-foot automated
callout.
• At 8:46:47, DCA tower cleared other jet traffic on Runway
1 for immediate
departure with no delay.
• At 8:47:27, or 32 seconds before impact, the Blackhawk
passed the southern
tip of Hains Point.
• A second later, the CRJ began a left roll to turn to final
on Runway 33. The CRJ
was at a radio altitude of 516 ft and 133 kts.
• At 8:47:29, the CRJ crew received a 500-foot automated
callout.
• At 8:47:39, or 20 seconds before impact, a radio
transmission from the tower
was audible on both CVRs asking the Blackhawk crew if the
CRJ was in sight.
Audible in the ATC radio transmission was a Conflict Alert
in the background.
• At 8:47:40, the CRJ crew received an automated traffic
advisory from the TCAS
system stating “Traffic, Traffic.” TCAS is the Traffic Alert
and Collision Avoidance
System on the CRJ.
• At 8:47:42, or 17 seconds before impact, a radio
transmission from the tower
was audible on both CVRs directing the Blackhawk to pass
behind the CRJ.
CVR data from the Blackhawk indicated that the portion of
the transmission
that stated “pass behind the” may not have been received by
the Blackhawk
crew. Transmission was stepped on by a 0.8 second mic key
from the
Blackhawk. The Blackhawk was keying the mic to communicate
with ATC.
• In response, at 8:47:44, the Blackhawk crew indicated that
traffic was in sight
and requested visual separation which was approved by DCA
Tower. The
instructor pilot then told the pilot flying they believed
ATC was asking for the
helicopter to move left toward the east bank of the Potomac.
4Feb. 14, 2025, NTSB Briefing Points on Mid-air Collision
near DCA
• At 8:47:52, or 7 seconds before impact, the CRJ rolled out
on final for runway 33. The CRJ was at a radio altitude of 344 ft, 143 kts.
• At 8:47:58, or 1 second before impact, the CRJ began to
increase its pitch, reaching about 9 degrees nose up at the time of collision.
FDR data showed the CRJ elevators were deflected near their maximum nose up
travel.
• The last radio altitude recorded for the CRJ was 313 ft
and was recorded two seconds prior to the collision. The CRJ pitch at this time
was, again, 9 degrees nose up, and roll was 11 degrees left wing down. The CRJ
was descending at 448 feet per minute.
• The radio altitude of the Blackhawk at the time of the
collision was 278 feet and had been steady for the previous 5 seconds. The
Blackhawk pitch at the time of the collision was about a half degree nose up
with a left roll of 1.6 degrees. Examination of wreckage will assist in
determination of the exact angle of the collision.
• We are confident that the radio altitude of the Black Hawk
at the time of the collision was 278 feet. I want to caution this does not mean
this is what the Black Hawk crew was seeing on the barometric altimeters in the
cockpit.
• We are seeing conflicting information in the data, which
is why we aren’t releasing altitude for the Blackhawk’s route.
- The CRJ’s
cockpit voice recorder has now been downloaded and read out. All times
listed in Eastern Standard Time —
- 20:45:27: CRJ
Autopilot off
- 20:46:01: ATC
makes PAT25 aware of CRJ south of the Wilson Bridge
- 20:46:29:
1000’ call out on CRJ
- 20:47:29: 500’
call out on CRJ
- 20:47:39: ATC
asks if PAT25 has the CRJ in sight
- 20:47:40:
TRAFFIC TRAFFIC aural alert sounds
- 20:47:42: DCA
Tower directs PAT25 to pass behind the CRJ
- 20:47:58: CRJ
crew has verbal reaction and airplane begins to increase its pitch
- 20:47:59:
Sounds of impact
- There were 5
air traffic controllers in the DCA tower at the time of the accident
- 1 Local controller working fixed wing and helicopter traffic
- 1 Ground
controller
- 1 local
assistant controller
- 1 Supervisor
- 1 Supervisor
in training
- The CRJ’s
cockpit voice recorder has now been downloaded and read out. All times
listed in Eastern Standard Time —
- 20:45:27: CRJ Autopilot off [Piloto Automático do
avião foi desligado]
- 20:46:01: ATC makes PAT25 aware of CRJ south of
the Wilson Bridge [Controlador
de Tráfego Aéreo alerta o piloto do helicóptero acerca do avião ao sul da
ponte Wilson]
- 20:46:29: 1000’ call out on CRJ [o Sistema de automático de
alerta de altitude do avião anuncia que a aeronave está 1000 pés acima da
superfície da água]
- 20:47:29: 500’ call out on CRJ [o EGPWS alerta que o avião
está 500 pés acima da superfície da água]
- 20:47:39: ATC asks if PAT25 has the CRJ in sight
[o Controlador de Tráfego
Aéreo pergunta ao piloto do helicóptero se ele tem na visão dele o avião]
- 20:47:40: TRAFFIC TRAFFIC
aural alert sounds [o
Sistema de Alerta de Colisão entre Aeronaves dispara o anúncio TRÁFEGO,
TRÁFEGO]
- 20:47:42: DCA Tower directs PAT25 to pass behind
the CRJ [o Controlador de Tráfego
Aéreo instrui o helicóptero para passar por trás do avião]
- 20:47:58: CRJ crew has verbal reaction and
airplane begins to increase its pitch [o piloto do avião reage verbalmente e inicia o aumento de
inclinação do nariz do avião para cima]
- 20:47:59: Sounds of impact [ouve-se o ruido da colisão
das duas aeronaves]
- There were 5
air traffic controllers in the DCA tower at the time of the accident
- Havia 5 Controladores de Tráfego Aéreo na hora do acidente:
- 1 Local
controller working fixed wing and helicopter traffic
[Um Controlador
local trabalhando no tráfego de aeronave com asa fixa(avião) e helicóptero].
- 1 Ground
controller
[Um Controlador
de tráfego no solo]
- 1 local
assistant controller
[Um Assistente de Controlador]
- 1 Supervisor
[Um Supervisor]
- 1 Supervisor
in training
[Um Supervisor em treinamento]
According
to an Army report, the service began issuing night-vision devices to its
aviators in 1985 and has continually acquired goggles that allow pilots and
aircrew to see more clearly and with better depth perception at night ever
since.
Recent Army-wide standardization inspections and accident
investigations have revealed deficiencies in maintenance and use of night vision
goggles (NVGs) and the Aviator’s Night Vision Imaging System (ANVIS). The
purpose of this article is to clarify requirements for modification, inspection,
and use of AN/PVS-5 series NVGs and the ANVIS-6.
AN/PVS-5 series NVGs Modification. Only two modifications are authorized for ANI
PVS-5 series NVGs used in aviation operations. One is the modified faceplate
(MFP) described in the U.S. Army Aviation Center booklet:
AN/PVS-5, 5A Night Vision Goggle Aviator Modifications, dated 10 Jun 83.
The other modification authorized for AN/PVS-5 NVGs in aviation
use is the GX-5 flip-up described in an April 1987 booklet published by the
Aviation Life Support Equipment Project Manager’s Office, Aviation Systems
Command (AVSCOM).
The Air Traffic Controller's radar screen demonstrates that
there is NO PRECISION for each aircraft geographical position in the target presentation
on the radar screen. The targets are shown as if the helicopter had already passed
behind the CRJ7 plane. In conclusion, the ATC see the target in FALSE position.
There is an ERROR between the target shown on radar screen and the real
aircraft position.
In the next second, the plane descends 300 feet and collides with the helicopter.
