Large Commercial Aircraft Down

maus92

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If you are talking about "exempts helicopters entering this airspace for lifesaving medical support, active law enforcement, active air defense, or presidential transport helicopter missions," those are typical exemptions for any airspace. Active law enforcement would be USPP, DC, MSP, PGC police missions; various Medevac provider missions; air defense would be USCG MH-65s that enforce the SFRA; and of couse Presidential flights. What this will greatly affect are executive transports for general officers to/from the Pentagon, which makes up a sizable chuck of helicopter traffic along the Potomac, and training for those.
 

BinaryMode

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What does that mean? The Blackhawk was on a training flight and they were in contact with the DCA tower the whole time. All airspace in the DC area is positive control which means you are always talking to ATC wherever you are flying. Military, law enforcement, and medical helos transition this airspace all the time and what the flight the Blackhawk was doing is extremely common in that area.

It means, and in my humble opinion that military choppers should not be training along the flight path of a landing...



I really don't know what you are asserting or speculating about here.

Sorry about being esoteric. Watch what happens in the coming years...



TCAS doesn't issue alerts (RAs) below 900 Feet above the ground.

Correct, and I think it's 1,000 AGL. But the CRJ should have gotten a TA... Especially since the helicopter was using Mode-S and the TCAS II in the CRJ would pick it up.
 

MUTNAV

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Does anyone know off hand if the helicopter is equiped with a a radio altimeter, the kind that 5G was interfereing with?

Thanks
Joel
 

maus92

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Does anyone know off hand if the helicopter is equiped with a a radio altimeter, the kind that 5G was interfereing with?

Thanks
Joel
UH-60Ls do have radio/radar altimeters although they are LPI so who knows if they are susceptible to 5G interference. Basically a moot point however since they were operating where the terrain is flat, and the wx was clear. They are typically used to avoid the ground, not to limit altitude.
 

MUTNAV

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UH-60Ls do have radio/radar altimeters although they are LPI so who knows if they are susceptible to 5G interference. Basically a moot point however since they were operating where the terrain is flat, and the wx was clear. They are typically used to avoid the ground, not to limit altitude.
I still "smell" the possibility of a problem.

This is kind of informative.

Aircraft Operations and Radar Altimeter Interference from 5G - ALPA

They mostly address the problem of doing instrument approaches. I can easily imagine an aircrew using it to make sure they are staying at or under 200ft with one.

Thanks
Joel
 

maus92

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I still "smell" the possibility of a problem.

This is kind of informative.

Aircraft Operations and Radar Altimeter Interference from 5G - ALPA

They mostly address the problem of doing instrument approaches. I can easily imagine an aircrew using it to make sure they are staying at or under 200ft with one.

Thanks
Joel
(Baro) altimeter is the primary altitude reference instrument which works on atmospheric pressure, not radio signals bouncing off the surface. I suppose the helicopter crew *could* have forgotten to adjust it for the current pressure.
 

BinaryMode

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Looking at the video I uploaded again, the helicopter is shown climbing then descending right until the collision.
 

MUTNAV

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(Baro) altimeter is the primary altitude reference instrument which works on atmospheric pressure, not radio signals bouncing off the surface. I suppose the helicopter crew *could* have forgotten to adjust it for the current pressure.
I was able to find the manual for the UH-60 (including L varient) and they have a radar altimiter that has a high and low "bug" setting that they can use to alert them if the get too high or too low.

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Joel
 

maus92

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I was able to find the manual for the UH-60 (including L varient) and they have a radar altimiter that has a high and low "bug" setting that they can use to alert them if the get too high or too low.

Thanks
Joel
You are assuming that it was in use in the mode that you imply. It really doesn't matter as the RA is not the primary altitude instrument. At most, it would function as a reminder to the crew to pay attention to altitude - which at the very least they could visually track.

Adding: if "5G" is a culprit as you suggest, would you not think that discrepancies would have been detected in the past as there has been 10s of thousands of UH-60 flights in the area since 5G was introduced. Certainly this would be the case, and procedures would have been devised to mitigate the issue - if it even exists.
 
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MUTNAV

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You are assuming that it was in use in the mode that you imply. It really doesn't matter as the RA is not the primary altitude instrument. At most, it would function as a reminder to the crew to pay attention to altitude - which at the very least they could visually track.

Adding: if "5G" is a culprit as you suggest, would you not think that discrepancies would have been detected in the past as there has been 10s of thousands of UH-60 flights in the area since 5G was introduced. Certainly this would be the case, and procedures would have been devised to mitigate the issue - if it even exists.

I'm not really "suggesting" or "assuming" anything... A little lower than that, even lower than "guessing", the level I'm at is probably best described as "wondering".

I'm sure the Radar altimeter exists for a reason, and could be referenced, they are used for some CAT II and III ILS approaches. I don't remember a -reminder- setting on any altimeters I've seen.

The RA has the upper and lower limit bugs that I would think would be very helpful when the instructions say to stay below 200'.

If they did (and I'm not even suggesting the were using the RA), then any procedures could have gone along with the procedures to, for example, "stay over the eastern shore" until further north, and stay below 200'.

5G couldn't have been the culprit in any case, since all radar altimeters were supposed to have to have been updated by now, at least for certain classes of aircraft.

It's one of the many many things for the investigators to look at.

We've actually had discussions about 5G and RA interference on RR, it was cleared up a while ago.

It was basically the same discussion as some satellite phones interfering with GPS... the discussion being that GPS was designed to work in a part of the spectrum that (was the equivalent of) zoning for a quiet residential area, and the SATCOM signals was the equivalent of having a rock concert in that zone (GPS receiver filters weren't meant to deal with the level of interference generated).

Hopefully nothing had slipped through the cracks.

BTW, I appreciate the discussion were having.


Thanks
Joel
 

BinaryMode

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And? Altitude departures can occur for any number of reasons.

I was just stating the fact from the captured aircraft movements that the pilot is seen climbing and then descending - right into the approach path of the CRJ. Nothing more, nothing less.

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I want to reiterate something here. There should be absolutely no reason once so ever, training or otherwise for an aircraft ( a helicopter in this case) to be nonchalantly in the approach path of an aircraft - EVER! Especially, ESPECIALLY DCA which is a very busy airport and in fact has become busier thanks to politicians.

In my opinion, I think the ball was dropped from multiple fronts and common sense may have went right out the window. Like Bruce Hornsby once sung, and Home Depot used for advertisement circa 2006, "there's gonna be some changes made."

If I were a commercial airline pilot I'd personally get the heebie-jeebies knowing that a helicopter could be in or near my approach profile. With that being said, it seems more prudent now than ever that one should want to pay more attention to the TAs just as much as the RAs.

I just want to post that this should have never happened and should never EVER happen again. And I feel a sense of sadness for those involved, especially Nancy Kerrigan and all that talent that we lost. And we have all probably thought in the back of our mind that could have been one of us or a family member or friend. Again, this should have never have happened. Rare is it that aircraft have accidents let alone a mid-air collision. Especially since that day in San Diego in 1978 of a mid-air collision and other mid-air collisions at the time made the FAA mandate all aircraft flying at or below FL100 go no faster than 250 knots unless instructed otherwise by ATC. That crash also instituted what is now class B airspace. This was a very pivotal moment in aviation history and I feel the same way about this Potomac mid-air collision.
 

maus92

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I was just stating the fact from the captured aircraft movements that the pilot is seen climbing and then descending - right into the approach path of the CRJ. Nothing more, nothing less.

-------------------------------------------------------------------------


I want to reiterate something here. There should be absolutely no reason once so ever, training or otherwise for an aircraft ( a helicopter in this case) to be nonchalantly in the approach path of an aircraft - EVER! Especially, ESPECIALLY DCA which is a very busy airport and in fact has become busier thanks to politicians.

In my opinion, I think the ball was dropped from multiple fronts and common sense may have went right out the window. Like Bruce Hornsby once sung, and Home Depot used for advertisement circa 2006, "there's gonna be some changes made."

If I were a commercial airline pilot I'd personally get the heebie-jeebies knowing that a helicopter could be in or near my approach profile. With that being said, it seems more prudent now than ever that one should want to pay more attention to the TAs just as much as the RAs.

I just want to post that this should have never happened and should never EVER happen again. And I feel a sense of sadness for those involved, especially Nancy Kerrigan and all that talent that we lost. And we have all probably thought in the back of our mind that could have been one of us or a family member or friend. Again, this should have never have happened. Rare is it that aircraft have accidents let alone a mid-air collision. Especially since that day in San Diego in 1978 of a mid-air collision and other mid-air collisions at the time made the FAA mandate all aircraft flying at or below FL100 go no faster than 250 knots unless instructed otherwise by ATC. That crash also instituted what is now class B airspace. This was a very pivotal moment in aviation history and I feel the same way about this Potomac mid-air collision.
I have to respectfully disagree with your proposal to ban helicopter flights in approach paths. I have flown on Route 4 with commercial traffic landing at DCA every two minutes in the past (pre-ADSB), and current experience along the Delaware River adjacent to PHL - however always in daylight. Helicopters operate in the airport environment and Class B airspace all the time, all across the country, and the world. It is not inherently unsafe if altitude separation is maintained, but it requires vigilance (aka see and avoid) and communication. I can see some changes due to this accident in procedures aboard helicopters and specifically military helicopters. 1> ADS-B equipage / usage mandatory in DCA Class B; perhaps only ADS-B-In for military OPSEC. 2> NVG usage: one flight crew member should not be on NVGs. 3> Routine training / re-qualification flights should not be conducted within a 3nm radius of DCA unless necessary to meet a mission-specific goal. 4> Consider combining tower frequencies for both fixed-wing and helicopters, or require helicopters to monitor both.
 

MUTNAV

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I have to respectfully disagree with your proposal to ban helicopter flights in approach paths. I have flown on Route 4 with commercial traffic landing at DCA every two minutes in the past (pre-ADSB), and current experience along the Delaware River adjacent to PHL - however always in daylight. Helicopters operate in the airport environment and Class B airspace all the time, all across the country, and the world. It is not inherently unsafe if altitude separation is maintained, but it requires vigilance (aka see and avoid) and communication. I can see some changes due to this accident in procedures aboard helicopters and specifically military helicopters. 1> ADS-B equipage / usage mandatory in DCA Class B; perhaps only ADS-B-In for military OPSEC. 2> NVG usage: one flight crew member should not be on NVGs. 3> Routine training / re-qualification flights should not be conducted within a 3nm radius of DCA unless necessary to meet a mission-specific goal. 4> Consider combining tower frequencies for both fixed-wing and helicopters, or require helicopters to monitor both.
Although I think your suggestions are decent... unfortunately, and it sounds like you were in the military, you know how it goes. A commander could have implemented lots of your good suggestions prior to the crash and it would have been fine... But since they weren't, the "powers that be" will do what they think is best, and it will probably be a little more extreme than the suggestions.

Radio wise... In the news they keep talking like the communications were duplex, vs simplex.... I have no information suggesting that. IS there a duplex arrangement for some ATC comms now?

Thanks
Joel
 

AK9R

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Radio wise... In the news they keep talking like the communications were duplex, vs simplex.... I have no information suggesting that. IS there a duplex arrangement for some ATC comms now?
I don't think theres any duplex. Aircraft inbound to DCA are on a different frequency from helos flying the helicopter routes. The only common point is, apparently, the DCA tower controller who talks on both frequencies.
 

MUTNAV

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I don't think theres any duplex. Aircraft inbound to DCA are on a different frequency from helos flying the helicopter routes. The only common point is, apparently, the DCA tower controller who talks on both frequencies.
Thats what I was pretty sure of, I don't know why news keeps on bringing up duplex communications.

Thanks
Joel
 

maus92

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I haven't read or heard anything specifically referring to "duplex" communications wrt this accident, however it would not be unusual for a tower controller to combine the both tower frequencies and the heli frequency during times of limited staffing. But this does not mean aircraft operating on the tower frequency would hear helicopters operating on their discrete, and vice-versa. We'll have to wait for more specifics to clarify how everyone's radios were configured.
 

MUTNAV

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I haven't read or heard anything specifically referring to "duplex" communications wrt this accident, however it would not be unusual for a tower controller to combine the both tower frequencies and the heli frequency during times of limited staffing. But this does not mean aircraft operating on the tower frequency would hear helicopters operating on their discrete, and vice-versa. We'll have to wait for more specifics to clarify how everyone's radios were configured.
Right, I had never heard of duplex air communications, which is what was suprising to me, I'm trying to find where I read it. No luck so far.... although there have been a LOT of really off base comments.

Thanks
Joel
 

BinaryMode

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I had a discussion about "apparent" duplex communication with the civilian and military guard frequencies of 121.5 and 243.0 MHz respectively here in the aircraft subforum. I asked if civilian aircraft had access to 243 because I heard ATC on that frequency telling United or Delta or Southwest, etc to call such and such on such and such frequency. I couldn't understand that and neither did a former air traffic controller gaming friend of mine. It turns out that ATC does a simultaneous broadcast on 121.5 and 243.

Being Xenforo (this forum software) it's very hard to find my previous threads. I'll have to use what is called "Google dork" and see if I can find my thread from some time ago.

Edit-

And here's my thread. Read it entirely.
 
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