Garmin EFIS Failure Rates?

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

Toobuilder

Well-Known Member
Log Member
Joined
Jan 19, 2010
Messages
4,734
Location
Mojave, Ca
Frankly, I'm looking at dual AHRS/Dual screens (leaning seriously toward Dynon at the moment), AND a final, "hail Mary" backup like the Stratus, D1, or mini.

...And I don't really plan on routinely flying "hard" IFR unless it's close to an emergency. I'll pop through a layer to get on top, and maybe once again to get down, but flying three hours through the clag with an approach to minimums is not something I'm going to do in a homebuilt piston single.
 

TFF

Well-Known Member
Joined
Apr 28, 2010
Messages
12,851
Location
Memphis, TN
My friend flies his 7 IFR often, but not hard to minimums, unless he is really stuck and cant wait it out. He has lots of free time between work days, so he can usually wait a couple of days to get home. Not fun but he will fly clouds all the way if needed. He is not into flying to mins but he does practice it and with WAAS coupled to his autopilot, you're only there to flair the plane. Our airport has pretty high mins without WAAS, because of some antennas, but WAAS knocks 600ft off the mins. It really makes the plane a traveling machine. The WAAS will fly the plane to the threshold. It is probably more accurate than an airliner with Cat II capability, if allowed. Across the way another buddy cheeped out and did not put a IFR GPS in his 8 and he kicks himself all the time. I will say, there is an older 4 painted up like a P-51 and it has every round gauge known to man; looks like a real P-51 cockpit; he is old and crusty and will fly it hard hard IFR, but he also had ejected from a plane so he's not to scared of much when it comes to flying.
 

SVSUSteve

Well-Known Member
Joined
Aug 20, 2007
Messages
3,894
Location
Evansville, Indiana
he is old and crusty and will fly it hard hard IFR, but he also had ejected from a plane so he's not to scared of much when it comes to flying.
Oddly enough, I think I have the guy you're talking about. We have a RV-4 which comes into one of the airports up here all the time from down around Memphis. The pilot is a this cranky old former Marine pilot. The RV-4 I'm talking about looks like one of the instrument manufacturers sponsored his cockpit. LOL
 

bmcj

Well-Known Member
HBA Supporter
Joined
Apr 10, 2007
Messages
13,357
Location
Fresno, California
Perhaps the issue isn't the failure rate, but the pilot training on how to fly in the event of a failure. This is an excerpt from a story about a Piaggio Avante crash. Though there were several mistakes made by the crew that contributed to the accident (very poor overall decision making by the crew), The part I found most interesting was that during an instrument failure, no one thought to reference the magnetic compass for actual heading information.

Circumstances

During climb to cruise, the captain increased left engine power and the engine power lever became jammed in the full forward position. This condition resulted in an engine overtorque and overtemperture condition, and the captain shut down the left engine. After the engine shutdown, both primary flight display screens went blank. The captain reset the right generator and the flight displays regained power and display. Due to the engine shutdown, the captain diverted to a nearby airport and attempted a single-engine precautionary landing in visual flight rules conditions. Based on wind conditions at the airport (290 degrees at 18 knots), runway 27 was being used for operations. During the descent, the crew became confused as to their true heading and were only able to identify runway 27 about a minute before touching down due to a 50-degree difference in heading indications displayed to the crew as a result of the instrument gyros having been reset. Accurate heading information would have been available to the crew had they referenced the airplane’s compass. Having declared an emergency, the crew was cleared to land on any runway and chose to land on runway 18. After touchdown, the captain applied reverse thrust on the right engine and the airplane veered to the right. The airplane flight manual’s single-engine approach and landing checklist indicates that after landing braking and reverse thrust are to be used as required to maintain airplane control. The airplane continued to the right, departed the runway surface, impacted terrain, flipped over, and came to rest inverted. At the point of touchdown, there was about 5,000 feet of runway remaining for the landing roll. The loss of directional control was likely initiated when the captain applied reverse thrust shortly after touchdown, and was likely aggravated by the strong crosswind. Postaccident examination of the airplane showed a clevis pin incorrectly installed by unknown maintenance personnel that resulted in a jammed left engine power lever. No additional anomalies were noted with the airplane or engines that would have precluded normal operation.


Causes

The captain's failure to maintain directional control during landing with one engine inoperative. Contributing to the accident was an improperly installed clevis pin in the left engine power lever, the crew’s delay in accurately identifying their heading, and their subsequent selection of a runway with a strong crosswind.


Final Report

http://www.baaa-acro.com/wp-content/uploads/2013/11/N168SL.pdf
 

TXFlyGuy

Well-Known Member
Joined
Apr 25, 2012
Messages
1,736
Location
Republic of Texas
There have been a couple cases where a professional crew, after losing primary flight display information, simply failed to check the standby attitude indicator. In the plane that I fly, 90% N1 and 2.5 degrees nose up will maintain altitude and airspeed, even without reference to AS or altimeter info. Knowing your aircraft is a big help.

EFIS failures are extremely rare.
 

SVSUSteve

Well-Known Member
Joined
Aug 20, 2007
Messages
3,894
Location
Evansville, Indiana
There have been a couple cases where a professional crew, after losing primary flight display information, simply failed to check the standby attitude indicator
Korean Air at Stansted, the Copa crash in the Darien Gap....any others?

In the plane that I fly, 90% N1 and 2.5 degrees nose up will maintain altitude and airspeed, even without reference to AS or altimeter info. Knowing your aircraft is a big help.
That's one of the things I would want to determine during flight testing.
 

TXFlyGuy

Well-Known Member
Joined
Apr 25, 2012
Messages
1,736
Location
Republic of Texas
Korean Air at Stansted, the Copa crash in the Darien Gap....any others?



That's one of the things I would want to determine during flight testing.
AF 447...although they had good info after the first 30 seconds was over. They simply did not believe their instruments. I doubt if they ever looked at the SAI. That is why I always make a mental note of power settings, pitch attitude, and the resulting airspeed.
 

SVSUSteve

Well-Known Member
Joined
Aug 20, 2007
Messages
3,894
Location
Evansville, Indiana
AF 447...although they had good info after the first 30 seconds was over. They simply did not believe their instruments. I doubt if they ever looked at the SAI. That is why I always make a mental note of power settings, pitch attitude, and the resulting airspeed.
Yeah, I remember one of my friends from the AAIB pointing out relatively early on that there's a way to fly the heavies strictly by pitch and power without ASI input. Although I don't think AF 447 had reliable standby information for those first critical moments (I could be wrong....it's been a while since I read the investigation reports) so the comparison would have been meaningless because the ADIs would have still had accurate information to allow them to maintain control. It was just the airspeed readings that were screwed up. I was thinking more along the lines of corrupted pitch and roll data like in the Stansted and Copa disasters.

Once the icing cleared and you have three systems giving you the exact same numbers AND the aircraft is behaving like you would expect (dropping like a stone) with those numbers, it's unforgivably stupid to not believe them.

Fear is a real cold-hearted b***h some times.
 

TXFlyGuy

Well-Known Member
Joined
Apr 25, 2012
Messages
1,736
Location
Republic of Texas
They were getting good flight data after about 40 seconds. If they simply would have left everything alone, they would have been fine. The airplane was on speed and in trim. But the First Officer (IRO) pulled the nose up 15 degrees...you would never ever do that in a transport aircraft while at FL330.

The rest is history as they descended at 8000 fpm in a flat attitude. It would have been confusing as they were bombarded by multiple warnings and cautions. It was salvageable, however, had they lowered the nose. Fully stalled right up until splashdown.
Tragic does not come close to describing the situation.
 
Top