The House will consider a bill that would ultimately require all aircraft that must now be equipped with TCAS (traffic alert and collision avoidance system) to have a newer, more sensitive version of the system called ACAS-Xa (airborne collision avoidance system Xa) installed. It’s the ALERT (Airspace Location and Enhanced Risk Transparency) Act. The bill, introduced by Missouri Republican Rep. Sam Graves, chairman of the House Transportation Committee, and ranking member Rick Larsen, D-Wash., late last week, is the House’s proposal to address recommendations from the NTSB arising from the collision between an Army Black Hawk helicopter and an American Eagle CRJ700 at Reagan National Airport on Jan. 29, 2025. In that report, the NTSB found that had the RJ been equipped with ACAS-Xa, the crew would have been warned of the impending collision about eight seconds before impact instead of the one second they got from the TCAS. The RJ didn’t have ADS-B In and the ADS-B Out on the helicopter wasn’t working.
ACAS-Xa uses the same basic technology as TCAS, but its advanced algorithms provide more accurate resolution advisories when it detects potential conflicts. The bill would first see it required for new aircraft mostly in transport and charter categories. There are also measures for DCA in particular to address the many shortcomings uncovered during the NTSB’s massive probe into operations there. The bill also includes actions to be taken by the Department of Defense with helicopter operations. The bill has been referred to committee for further work. Below is a presentation prepared by the FAA on ACAS-X.
It is complicated. Separation is not one box or one rule. It is layers: ATC procedures, surveillance, radios, navigation performance, cockpit displays, and last-ditch logic like TCAS/ACAS. The ALERT bill mainly adds stronger onboard logic and wider traffic receiving, but that also adds monitoring and potential distraction in the busiest phases. The net gain depends on implementation: good audio cues, minimal heads-down time, clear SOPs, and training that keeps eyes outside when it matters. Done right, it reduces surprise conflicts.
Agree. I get concerned when enhanced sensitivity is spec’d without similar or greater emphasis on selectivity. Sensitivity without selectivity = excessive false alarm rates which then get addressed by the human component ignoring, muting or disabling the distraction to regain a sterile cockpit in critical phases of flight.
We like to say “it’s complicated.” But how complicated is it to avoid putting a helicopter route directly in the path of landing traffic?
Instead, we keep layering on more technology, more alerts, more monitoring, more systems until the layers themselves become part of the risk. At some point, complexity stops adding safety.
ADS-B was deployed not to preserve the separation margins we already had. It was largely justified as a way to enable tighter airspace utilization. That may improve throughput, but it does not automatically improve safety, especially if the underlying procedures and deconfliction practices aren’t disciplined and protected.
Before we mandate yet another box in the cockpit, we should make sure we are rigorously using, maintaining, and enforcing the systems and procedures already on the books, and perhaps, remove those that simply complicate the procedure. Strong fundamentals, consistently applied, still beat layer-upon-layer of theoretical protection.
So let’s add another system that may not be working! I think they should concentrate on keeping existing systems working first or make a reg that if it isn’t working you don’t fly!
“The RJ didn’t have ADS-B In and the ADS-B Out on the helicopter wasn’t working.” – ADS-B has been around long enough and prices have fallen far enough that neither of these aircraft had any justifiable reason to be dispatched or operated in the very high density airspace where the collision happened. Even in the ’46 Navion I used to own, ADS-B displayed a very scary airspace on the Fisk Arrival for Air Venture, but was pretty darn useful.
I agree with that. Maintaining the current equipment would sure help, when operating in high traffic areas.
https://www.youtube.com/watch?v=I8PUtx-6_HY
Let me guess. This next system they want to legally require everyone to install for our safety of course, requires a load manifest with the names, social security numbers and real ID of every passenger on board so they can accurately identify the names of the crash victims. Maybe they could also put a camera in the cabin to see who gets off at which destinations and attach another datalink to their cell phones so that the IRS can accurately assess the taxes for passenger legs flown. It worked so well with ADSB that FBO’s have learned they can assess landing fees in this manner without anyone even being present to flag pilots into the blocks. But it’s all for our safety of course.
This may be simply a problem with the graphic and/or narration, but as the pilot of an aircraft that is represented by the C172 in the middle of the graphic, I’d like to know more about how the ACAS-Xr/-Xu – equipped vehicles are going to detect my presence. My fiberglass single-place Experimental helicopter is not (nor has it ever needed to be) transponder equipped, and frankly, does not have a sufficiently-robust electrical system to allow one to be retrofitted.
My chopper makes plenty of noise, so I never have a problem with organic flying machines, but the explanation of this proposed solution seems inadequate.
Without an approved deviation, your transponderless experimental helicopter is not permitted in airspace where operations typical of “aircraft that must now be equipped with TCAS” happen anyway, so it’s mostly a non-issue for you. Such aircraft, with few exceptions, don’t belong in crowded transport category dominated B/C airspace anyway. I can’t imagine you would even want to frequent your local international airport in that.
The title of the graphic is “Whole Airspace Protection”, yet I see nothing that indicates the ACAS-equipped airliner has any way to sense my “non-transponder” single-engine C172 flying in class G airspace, much less my nearly radar-invisible helicopter. So much for the “whole airspace” assertion.
What we have here is a failure to communicate, and now we’ve got three layers in the oven. Because the long-standing plan has basically been “see and avoid… harder.”
ROTOR (Visibility layer): Stop running busy airspace like a stealth exercise. If you’re in the mix, you squawk and you broadcast so you actually paint on everyone’s picture. Especially rotorcraft and government or military ops. Fewer pop-up targets, fewer last-second “traffic, twelve o’clock,” and less ATC guesswork.
ALERT (Safety-net layer): When the geometry still goes bad, the box gets smarter. Earlier, clearer advisories and, if needed, a “do this now” before it turns into aluminum confetti. It’s not separation service. It’s the airbag, not the steering wheel.
DFR (Upstream traffic-management layer): Down low, 0–400 ft AGL, quit pretending it’s empty just because it’s inconvenient. Put drones in lanes and volumes, require position plus intent, and make them deconflict by data early. Drones move. Manned aircraft fly the mission. Pilots shouldn’t be on short final playing “spot the quadcopter.”
And one more thing: I hope whoever designed that DCA corridor complex has retired by now.
A D I O S.
Trying to contain Far too much air traffic in tiny, restrictive airspaces just doesn’t cut it. New equipment is not going to fix this situation. They sold us the ADSB equipment we have with the same promises. Even if top military brass wasn’t pulling the circuit breakers on the equipment to hide all of their private transportation needs from prying websites, it just doesn’t work. The only real answer to restore safety is to reduce traffic flow.
Wow. What is seven seconds in that environment? Maybe if you had aerobatic aircraft?
There is a place where aircraft fill a -6 acft pattern arriving from holding overhead on their own initiative as flights of 2-4, entering at 350-450 KIAS, pulling 3-4 G’s crosswind to slow to gear speed downwind while keeping the pattern full to land every 45-55 secs until all are aboard. Helos safely operate alongside the fixed wing pattern.
It is done down to MVFR day and sometimes at night, not a word is spoken, visual separation is by each cockpit in 3/haze, no navaids, no radar, no TCAS, no ADS-B, no datalink, rarely with more than 2000 hrs/10 yrs experience, often much less than 1000 hrs/5 yrs experience in their early 20’s, oh and the “airfield” is moving and sometimes changing heading often towards the only clouds/rain in the area. There may be no divert in range and even if there is, fuel state is only a couple passes from an emergency and unique acft configurations/loading may add to the fun.
What makes all this possible is a respect for hard learned lessons, rock solid procedures, continuous training tailored to the environment and openness to input from the most junior participant with a good idea. It is not tech.
Tech can help when sound basics, procedures and training are in place and respected…without these, no amount of tech can alter the inevitable bad outcome.