A life's (fatal) lesson on how NOT to maintain magnetos

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67Dart273

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I ran across this guy when searching for info on the terrible air -to-air float plane crash this summer.

These videos deal with the tragic loss of the "was" gorgeous "909" B-17 and LOSS OF LIFE.

The last video shows some pretty bad examples of "how not to maintain" magnetos, whether your lawn mower, old OMC outboard, or A/G dragster.........or your "hobby" warbird

BEAR IN MIND that these guys GET YOU to donate money TO GO FOR A RIDE!!!

The last video first



The first video



In the following photos, investigators found BIG BIG problems with BOTH mags on the no4 engine.
One "P lead" (primary lead) is pulled out of the left mag far enough that the "safety" grounding tab GROUNDED THE MAG, disabling that mag

The points on the right mag WERE ONLY GAPPED at .006"

Additionally, investigators found weak condensers and coils on both mags, and one mag had the cam lobe worn below specs meaning that even if they had been "operating" the spark would have been marginal

In addition, plug gaps were excessive, and evidently required plug maintenance was lacking

First photo below is illustrating the "almost none" points gap on one mag. There are other problems

rightmagPoints.jpg


rightmag.jpg

Below, "P lead" pulled out of mag. This lead goes to the "kill" switch in the cockpit and grounds/ kills the mag in "off." In this case a "safety" device engaged, killing the mag. The safety device is held off when the 'P lead' is properly inserted and installed
LeftmagP_lead.jpg

Below, this last photo showing the "safety" device which grounds the points if the "P lead" (primary lead) gets pulled out of the mag. The "safety" part is that the P lead grounds the mag to "kill" it just like on a lawn mower. You would not want to not be able to shut down an engine, right? But in this case it cause deterioration of engine performance because this mag quit working at some point, as the safety contact grounded it
leftmagground.jpg
 
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Very interesting, but sad. I did not know the plane was maintained by volunteers.
I almost took my veteran uncle for a flight as a gift on Memorial Day near Lakewood NJ a few years ago. We never did make it.
He loved those old B-17 birds.
 
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I actually boarded that plane a few years ago in Melbourne FL. Those are awesome old air planes. I new they where all volunteered crews. But you would think they had some professional maintenance people.
20201221_202328.jpg
 
Really, very cool. I remember it cost a few hundred to go up for a spin and back to the airport.
You would think it was maintained better but that cost $.
They used to fly with the companion B-25, all bright aluminum, on special occasions.
A great sight to see.
 
Murphy’s law! Its a shame, loss of life and a national treasure was lost. But **** happens. Some is preventable.

Back in the 70’s I got my A&P license, you’d be surprised at some of the things that guys do for repairs. A second set of eyes to check over one’s work is a must.

Thanks for sharing the videos of the NTSB’s report. I hadn’t seen their version.
 
I went for a flight in the radio room of one a few years ago. As an old guy that when a teen, there was still WWII surplus radio/ electronics gear available surplus, I'm quite familiar with the radio gear on those birds
Below, "tuning units" for the BC-375 series transmitter. Each unit covers a "band" of frequencies, and plugs into the front of the transmitter
_MG_4895cs.JPG


Below, BC-375 transmitter. The high power high voltage for the tubes as well as smaller units for the receiver(s) were generated by "dynamotors." These were a coined name for a unit that was a DC motor with a generator wound on the same shaft. They had a set of brushes on each end. One end ran the motor, and the other took the generated voltage output. These came in many sizes AND WEIGHTS!!! and generated many many different voltages.

In the post WWII surplus era, when TV came into popularity, these old transmitters were unlovingly referred to as "TVI generators" (TV interference). They were poorly shielded, and the design which ran the PA (power amplifier) typically in "class c" amounted to an non-linear RF device which produced MANY spurs and harmonics

_MG_4894cs.JPG


Below, Browning machine gun above the radio room. This hatch was opened to man it, and the hatch also served as "escape" when needed

_MG_4893cs.JPG

Below, if I ever decide to ride on one of these girls again, I will pay more attention to this!!
_MG_4892cs.JPG
 
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My son and I (Both IA holders) own and operate an aircraft maintenance shop here in Arkansas. (KELD) I've been maintaining aircraft for over fifty years, my son has 23 years of experience. We maintain the majority of the planes based at our field and we perform flight line maintenances for the local airlines. We could both write a book about some of the "nightmare stuff," done by owners, we have found on planes that come to us for maintenance and inspections from other airports. I would be proud to say, that all of our regular customers are straight shooters. They leave the maintenance up to us. 14 CFR 43.3 Is clear about who and what a registered owner can do (preventive) to his or her aircraft. The scary pilot / owner is the one who has the "it's my damn plane and I'll do what I want to," attitude. Most owners respect the A&P /IA. In the case of the B-17 crash...those volunteers had to of had in their possession a mechanic's certificate or have worked on the B-17 under the "direct supervision" of a person with a mechanic's certificate (A&P) who was "experienced" in performing the particular maintenance the volunteer is doing under his or her supervision. You are subjected to an enormous amount of liability and responsibility supervising "un-licensed" persons. Even when I or my son perform maintenance or inspections on our own plane...he follows up on me and I return the favor. When operating an aircraft..."you can't pull over and lift the hood."
 
Good information.
Im sure someone's head is gonna roll as a result of these findings.
 
Prob comes down to skill and luck.
Not sure what a pilot could do if you loose an engine as you are about to land?
 
Those birds could fly on 2...why did it crash on 3?
Fuel load, (weight of the aircraft) airspeed management, with power loss, (maybe more than one engine), turning back to the field (causing further loss of airspeed and altitude) and propeller feathering problems and altitude. A culmination of factors occurring at the same time. A lot of questions can be answered here.
NTSB Docket - Docket Management System
 
Prob comes down to skill and luck.
Not sure what a pilot could do if you loose an engine as you are about to land?

Should never have shut down either
Should have declared an emergency and caught the cross runway
 
Never, ever turn into the direction of a failed engine at low altitude. Same thing happened to a Puerto Rico ANG C-130 a few years ago. Took off with a failed engine (should have aborted) and then turned left into the failed engine. Crashed on video. Criminal maintenance practice. Prop governor should have been changed. Mechanic was caught saying he “didn’t give a ****.” Incompetence is everywhere. Sad
 
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There are videos, three of the flight's last few seconds in the Link I shared.(post 15) The plane struggled to fly the moment it broke ground. Obvious struggling due to the amount of nose up attitude.
 
I'm asking how loaded are these doing their fam-flights? Not like they are lugging 2 tons of bombs. No matter I guess, whats done is done, I'm sure I saw that plane fly over my house a few times being in the glide path of John Wayne Airport (SNA)
 
Those birds could fly on 2...why did it crash on 3?

Pretty sure I remember the report stating both engines 3 and 4 had been feathered (or attempted). Seems likely that #4 had quit and #3 was down on power. Or it could have been pilot error and #3 was feathered on accident.

That much asymmetric thrust while slowing on approach is a deadly combo. Loss of directional authority probably started the rightward yaw, which would likely also induce some right roll too. Any attempt to roll left would only increase drag on the right side as well.

With the right wing low and no power on that side, it's no wonder it took a hard right at impact. It's tragic that a building happened to be right there though.
 
The original '9 Oh 9' had a charmed life during WW2. Went on 140 bombing missions without loss of a crewman. Well beyond the norm in those dangerous days.
The replica plane also had an interesting history, built too late to be a part of WW2, was later flown by remote control through a couple of nuclear testing episodes to gather data. That got the plane so hot it was parked for years. It was said to be possibly the most complete and original example of a B17 in existence. The loss of that plane is not greater than the loss of life in the crash, but the loss of that plane was also huge.

Nine-O-Nine - Wikipedia
 
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From what I read, two of the magnetos on two different engines were messed up, not just one of them. These planes have a special exemption from most of the FAA regulations under a special "Part" of the U.S. Code of Federal Regulations, which meant that the volunteers were reporting the plane's maintenance to a special supervisor with the FAA in Florida, not through regular FAA channels, and that special supervisor went away for some reason (retired? transferred?) so there was nobody to report to for a long time, so the volunteers let maintenance get lax.
 
Sad to say, most of our old hot rods are better maintained than this priceless antique warbird was.

The FAA revoked the Collings Foundation's permission to carry passengers in March 2020 due to safety concerns, citing “notable maintenance discrepancies” and a failure to maintain a “a culture of safety” leading up to the fatal 2019 crash of the foundation's B-17G.
 
I'm asking how loaded are these doing their fam-flights? Not like they are lugging 2 tons of bombs. No matter I guess, whats done is done, I'm sure I saw that plane fly over my house a few times being in the glide path of John Wayne Airport (SNA)
About 10,000 pounds less than what the military rated them for. A few extra people weigh nothing compared to the normal bomb/ammunition load these planes could take off with.
 
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