Midair collision between Helicopter and CRJ (AA5342) at Washington (DCA)

[p--and--t]

The NVGs don't provide true colour vision, but the CRJ pilots probably did not use them. Colour vision issues in humans are complex and can substantially impact vision. Some modern systems, like specific digital night vision devices, use advanced image processing to simulate colour. These devices often combine low-light sensors with infrared illumination and apply algorithms to approximate colours, though the result is not valid for colour vision.

Would CRJ pilots (or any passenger plane pilots) ever wear NVGs?

Not something I have ever contemplated happening .

 

[RSD]

Would CRJ pilots (or any passenger plane pilots) ever wear NVGs?

Not something I have ever contemplated happening .

Not regular airlines - the Blackhawk helo pilot in this incident was reported to be wearing NVG's - I'm not sure how much help they would be though in low altitude in the middle of DC - given the loss of peripheral vision they might have been more of a hindrance than a help.

 

[jb747]

Would CRJ pilots (or any passenger plane pilots) ever wear NVGs?

Not something I have ever contemplated happening .

No, never.

 

[RooFlyer]

OMaaT posted this video from VASAviation of ATC etc the day before the crash, where a helicopter appears to be playing dodge'em with several arrivals into DCA. If I'm understand it correctly, two collision alerts within minutes of each other.

 

[moa999]

I'm understand it correctly, two collision alerts within minutes of each other.

All that explains is why the collision alerts are ignored.
Both the aircraft and the heli are following the river, but separation in those cases was over 1000ft - much further away from the runway threshold.

 

[VPS]

I find this amazing on the BBC website after the crash - there were some figure skaters on board so they show a picture of Torvill and Dean -WTF

Not wanting to take anything away from this terrible tragedy this guy is great

 

[Sprucegoose]

Mods can you please keep this thread on topic.

 

[drron]

Mods can you please keep this thread on topic.

And free of politics.

 

[Quickstatus]

For helicopter pilots:

What is the error range of altimeters?.
X00feet indicated = X 00 feet +/- actual?

How easy is it to maintain altitude at X?. Is there an allowed variability?

 

[markis10]

For helicopter pilots:

What is the error range of altimeters?.
X00feet indicated = X 00 feet +/- actual?

How easy is it to maintain altitude at X?. Is there an allowed variability?

Helicopter or fixed wing it’s fair to say they are the same ie highly accurate, but they require accurate local air pressure data which is why QNH is always mentioned. If the pilot does not have the right QNH dialled in, you get errors ….

 

[DejaBrew]

Question for the pilots/ATC folk on AFF -:

Various news outlets reporting that “…preliminary radar data has led investigators to believe the helicopter may have shown an altitude of 200 feet to controllers in the tower…” despite impacting with the CRJ at around 325 feet (give or take).

Any thoughts on what could cause this sort of misread (for want of a better term to use)?

 

[Quickstatus]

highly accurate

an error of (lets pick a number) - say +/-10 feet?

 

[markis10]

an error of (lets pick a number) - say +/-10 feet?

To quote the FAA

1. Barometric Pressure Altimeter Errors
   1. High Barometric Pressure: Cold, dry air masses may produce barometric pressures in excess of 31.00 “Hg. Many aircraft altimeters cannot be adjusted above 31.00 “Hg. When an aircraft's altimeter cannot be set to pressure settings above 31.00 “Hg, the aircraft's true altitude will be higher than the indicated altitude on the barometric altimeter.
   2. Low Barometric Pressure: An abnormal low-pressure condition exists when the barometric pressure is less than 28.00 “Hg. Flight operations are not recommended when an aircraft's altimeter is unable to be set below 28.00 “Hg. In this situation, the aircraft's true altitude is lower than the indicated altitude. This situation may be exacerbated when operating in extremely cold temperatures, which may result in the aircraft's true altitude being significantly lower than the indicated altitude.
      NOTE-
      
      EXTREME CAUTION SHOULD BE EXERCISED WHEN FLYING IN PROXIMITY TO OBSTRUCTIONS OR TERRAIN IN LOW PRESSURES AND/OR LOW TEMPERATURES.
2. Altimeter Errors
   1. Manufacturing and installation specifications, along with 14 CFR Part 43, Appendix E requirement for periodic tests and inspections, helps reduce mechanical, elastic, temperature, and installation errors. (See Instrument Flying Handbook.) Scale error may be observed while performing a ground altimeter check using the following procedure:
      1. Set the current reported airfield altimeter setting on the altimeter setting scale.
      2. Read the altitude on the altimeter. The altitude should read the known field elevation if you are located on the same reference level used to establish the altimeter setting.
      3. If the difference from the known field elevation and the altitude read from the altimeter is plus or minus 75 feet or greater, the accuracy of the altimeter is questionable and the problem should be referred to an appropriately rated repair station for evaluation and possible correction.
   2. It is important to set the current altimeter settings for the area of operation when flying at an enroute altitude that does not require a standard altimeter setting of 29.92 “Hg. If the altimeter is not set to the current altimeter setting when flying from an area of high pressure into an area of low pressure, the aircraft will be closer to the surface than the altimeter indicates. An inch Hg. error in the altimeter setting equals 1,000 feet of altitude. For example, setting 29.90 “Hg instead of 30.90 “Hg. To quote an old saying: “GOING FROM A HIGH TO A LOW, LOOK OUT BELOW.”

The weather at the time

KDCA 300152Z 30014G23KT 270V330 10SM CLR 10/M07 A2990

Aviation separation standards generally take errors into account if we are talking vertical sep, but it was visual sep being applied here.