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gpmtoday at 1:01 PM1 replyview on HN

Note that after the pilots said that they could go visual the preliminary report documents the following

> The ARTCC controller subsequently cleared the flight to SRR, cleared the flight for a visual approach, and informed them they could cancel IFR in the air above 9,000 ft msl or they could cancel their clearance via the flight service station after landing. The flight crew acknowledged the clearance and responded that they would cancel IFR “in just a couple of minutes.” There were no additional radio transmissions received from the flight crew.

It's not at all clear to me that they did go visual. They communicated that they intended to cancel instrument clearance later and that suggests they were still using it...


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bri3dtoday at 4:38 PM

That's not how this works, at all.

Visual approach is a specific IFR procedure. It's basically designed to expedite and simplify the landing process in situations where the pilot can see the airport and traffic allows - instead of flying a detailed set of waypoints provided by an approach plate (via RNAV/GPS, ILS/VOR/DME, or vectors), the pilot and ATC both agree "hey, you can see the runway and/or traffic, you got this now" and the pilot lands.

By asking for a visual approach and getting approved, then not subsequently asking for another approach, the PIC was flying visually. There's nothing more to it. There's no nuance or gotcha here, and nothing seems procedurally incorrect or even out of the ordinary.

"Canceling" IFR just means concluding the flight plan and "closing the file;" which they were given the option to do in the air or on the ground, but it's not relevant to the approach they chose to fly.

The root cause of this incident is clearly pilot error; the pilot specifically chose to fly a visual approach without adequate visual reference and descended into terrain.

There are proximate causes too, which may or may not relate to the GPS jamming and for which more information is required. For example - did the pilot choose to request the visual approach because they didn't want to fly an RNAV approach in case GPS was inaccurate, or because they didn't want to burden ATC? or did they just choose the visual approach because they could see the airport and it's easier that way? Was this in line with any guidelines from their operator? We don't know that yet. And there's some chance that without GPS jamming, a secondary safety system (GPWS, moving map, etc.) may have saved the pilots from their decision. But these things are all secondary.

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