Improper Use of ADS-B

[MrMorden]

Gizmos are cool, but use them properly and don't rely on them to save your bacon.


http://www.ntsb.gov/aviationquery/brief ... 3831&key=1

NTSB Identification: ERA12FA566
14 CFR Part 91: General Aviation
Accident occurred Monday, September 17, 2012 in Crane Hill, AL
Probable Cause Approval Date: 11/17/2014
Aircraft: MOONEY M20M, registration: N1085A
Injuries: 2 Fatal.

NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
The pilot initially delayed the cross-country flight for convective weather, but later took off, encountered weather in a climb, and advised an air traffic controller that he was looking at “ADS-B” (Automatic Dependent Surveillance-Broadcast). As the flight progressed, the airplane climbed to 13,000 feet, and the pilot asked the next controller if there were any reports of icing ahead about 15,000 feet. The controller noted no reports of icing, “but quite a bit of deviation, quite a bit of clouds and precipitation in front of you.” The pilot requested 15,000 feet “to see if I can see things better,” which was approved by the controller. Upon switching to the next controller, the pilot was advised of moderate to extreme precipitation for the next 90 miles. The pilot then stated that in looking at the ADS-B, he needed to deviate. Deviation was approved, and, 2 minutes later, the pilot advised the controller that he was making another deviation, which the controller acknowledged. Eighteen minutes after that, the controller told the pilot to change radio frequency, and the pilot responded, “unable, we’re battling some pretty bad...”. The airplane subsequently made numerous turns and altitude excursions, turning 90 degrees to the right and descending to 14,600 feet, then turning another 90 degrees right and descending to 14,100 feet. After making a sharp left turn, the airplane climbed to 15,500 feet, then made another sharp left turn, and, as it began a final rapid descent to the ground, the pilot issued several mayday calls. An examination of the wreckage revealed no mechanical anomalies that would have precluded normal operation.The expected ADS-B cockpit depiction compared to real-time, ground-based radar indicated significant differences in the depiction of hazardous reflectivity (rain). In the ADS-B product, the airplane was depicted as being clear of moderate or heavy rain as it made its final various turns. However, rea-time radar imagery indicated that the airplane would have been in or near moderate-to-heavy rain.The pilot indicated to the controller that he was using ADS-B in a tactical manner; however, ADS-B is intended to be used in a strategic manner . It is unknown why the pilot lost control of the airplane in moderate-to-heavy rain; he may have become confused and lost situational awareness when turning into what he thought were clearer conditions per the ADS-B depiction but was actually worse weather. ADS-B does not show what the weather is; it shows what the weather was up to 15 to 20 minutes earlier.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

The pilot’s loss of control in moderate-to-heavy rain. Contributing to the accident was the pilot’s reliance on ADS-B for tactical weather avoidance.

[Merlinspop]

Used improperly, they might actually cook your bacon instead of save it.

RIP to this pilot and his passenger.

[Wm.Ince]

Used improperly, they might actually cook your bacon instead of save it.

The same can be said for synthetic vision (i.e. scud running in areas of rapidly rising terrain).

[MrMorden]

Any technology is a two edged sword...great used properly, a menace used improperly!

Example: a chainsaw.

[CharlieTango]

Used improperly, they might actually cook your bacon instead of save it.

The same can be said for synthetic vision (i.e. scud running in areas of rapidly rising terrain).

Bill,

I think its an interesting question, can I, in an emergency, navigate through high terrain via synthetic vision?

I have had a few experiences and I think my experiences are interesting.

1) With a safety pilot and a hood is it intuitive to fly through high terrain relying on the SynVis presentation? Answer is it is pretty easy. Even easier than flying with a hood and Nav/Coms to guide you.
2) When presented with a transition from VMC to IMC is it just as easy? Answer is no, I find I maneuver excessively to preserve the visibility that I am reluctant to transition to syn vis.
3) Does it save your bacon? Answer is yes. I have been enveloped by forest fire smoke and relied on syn vis for 70 miles while below the terrain and it was uncomfortable but pretty easy. The flying wasn't the hard part for me the transition to IMC was.

[CharlieTango]

This is the terrain 1 mile south of our airport.




The thought of navigating it with syn vis appealing and after having an in panel nicely presented solution for 5 years+ I say it works, I could fly by it if I couldn't see and I could fly a 'syn vis' approach to any field using it.

The value to me is enormous.

[Wm.Ince]

. . . "can I, in an emergency, navigate through high terrain via synthetic vision?

The short answer is, not safely in IMC. Don't confuse GPS navigation with synthetic vision, they are not the same.
The operative word is "emergency." That is an unintended situation, agreed? Flying in marginal weather, regardless of terrain, is pushing the envelope. It is really, really pushing the envelope without being instrument rated.
If you plan flights, in marginal weather, using synthetic vision as a navigational tool, you are playing with fire.
It may seem very reliable, but synthetic vision was never intended to be used for that purpose. What's more, the vendors who produce it always provide a disclaimer to that affect.

In my opinion, using synthetic vision, with the intention to navigate in marginal weather, is not a safe operating practice.
That withstanding, I have plenty of instrument experience and experience transitioning from VMC to IMC, with or without recovery. However, that experience is not current, and I would not even contemplate it now.