There is no question as to who caused this midair collision. The helo was at 325' AGL.... 125' ABOVE the max altitude for that helo corridor (Route 1 to Route 4/200' or BELOW) . The question is WHY??

I don't know that I would call them rookies, with an almost combined 1500 flight hours... 1000 hours for the FI and almost 500 for the Pilot.

Could be a combination of several things... a minor deviation in the aircraft's altimeter IOM setting (which are manually set before each flight/airport) could easily have them 100ft or more in actual altitude. Something they likely would have easily recognized in daylight at that level, but at night over water probably not so much. Also, the way a rotary wing aircraft of that size/power is tuned and piloted, a pilot could sneeze and literally rise (or drop) 50ft due to the minor nerve/muscle tremor.

Not trying to make excuses for anyone, I mean it could be a training/knowledge issue just as well. But being 125ft off in altitude is not really hard to do in a rotor wing aircraft.

I would suggest people read the comments below the video. There are former helo pilots, one who flew that route something like 70 times and several controllers who commented. You are correct about the altitude but one of the commenters said something about them being able to go outside that when given visual separation rules. The helo pilot was asked to cross after the plane had gone by which lead me to believe they were looking at the wrong aircraft.

This is just conjecture but here are my thought:

The young Capt flying the helo had served as some kind of function, social something or other, with team Biden. With the new administration, she was sent back to the line. So she goes to the outfit that does continuity of government in DC. At the time of the crash my guess is that she was getting a night check out for this new mission.

Here the guess work gets deep. The UH60 does not have an autopilot. I think she was at the 200 feet ceiling...but when traffic was called everyone looks for traffic, it is second nature to pull back a tiny bit on the stick or collective, whatever they call it,..slow climb while pilots are looking for traffic.....boom.

I could be off...but this is my best guess...

The problem with many of the conclusions here is that the traffic controller had been talking to the helo pilot and several times was told they had eyes on the plane. Obviously that was not the case. Obvious to me anyway.

They did have visual contact....with which aircraft?

Thats the question. It seems apparent to me that the helocopter saw one of the planes landing on runway 01 and not the one the controller was asking them to look out for.
Planes were stacked up going into runway 01. The controller asked a plane earlier if they could divert to runway 33.
That plane said they couldn't so they were cleared for landing on 01. The controller then asked the plane that was in the collision if they could divert and they agreed to.

That video I posted had most of it in it with radar reconstructed from data he had gotten along with communications.
"(tower)Pat 25 (the helo) Traffic just south of the Wilson bridge is a CRJ at 1,200' for runway 33".
"(the helo)Pat 25 has the aircraft in sight, request visual separation".
"(tower) Visual Separation approved".

The tower came on later and asked again when they had gotten worried and the helo confirmed they had the plane in sight.

If you don't want to watch the whole video you can start around 8 minutes.
That shows how far away the plane was when the blackhawk first said they saw the jet. There were several other planes in the air and the helo pilot could have easily mistaken the planes lined up for 01 instead of the one plane that had been diverted.

https://youtu.be/RzQe6W7vcu4

Either way when the controller got the conflict advisory,he should have had the black hawk change heading and descend,not ask if he had it in sight.

Could have said, "PAT 25, CRJ at your 12oclock, three miles descending, Confirm traffic in sight."

That would have probably been enough to avoid a collision.

Who was the pilot?

Some DEI twit.

Thats shameful to me that you say that about someone who served with distinction just because.
She graduated in the top 20% of all ROTC members in the country. That does not sound like DEI to me.