On a crisp August morning in 2023, a vintage Boeing A75N1 (PT-17 Stearman) took off from Red Lodge Municipal Airport in Montana, its bright yellow wings glinting under the sun. The 76-year-old pilot and his passenger were looking forward to a scenic flight. But just moments after takeoff, their adventure took a dangerous turn when the aircraft, rather than climbing, began to sink toward the tree-covered terrain below.
The Flight That Didn’t Climb
At 9:00 AM, with light winds and clear skies, the Stearman lifted off from Runway 16. The aircraft, a classic biplane often used for training and leisure flights, initially seemed to perform normally. However, as it crossed a sharp drop-off in terrain—described by the pilot as a “steep hill about 200 feet”—the airplane inexplicably began to descend.
The pilot quickly ran through his checks. Throttle and mixture? Full forward. Ignition switch? Set to both. Fuel selector? Confirmed on. Despite these efforts, the aircraft continued its unwanted descent. There was no obvious reduction in engine noise, but the pilot knew he had little time to act. He focused on looking outside to find a suitable place to land rather than inside trying to determine what the tachometer was showing for an actual RPM reading.
From a mile away, a witness saw the biplane stop climbing, then begin its descent into the trees. Within seconds, the aircraft struck the treetops, nosed over, and came to rest—damaged but thankfully upright.
A Mechanical Mystery
With both the pilot and passenger escaping unharmed, attention quickly turned to what had gone wrong. A post-accident inspection revealed a troubling mechanical issue: the aircraft’s Bendix-Scintilla magneto, a crucial component of the ignition system, was not functioning properly.
Further examination uncovered multiple issues:
- One set of magneto points wasn’t opening and closing as it should.
- The advance-side coil had been improperly serviced, with loose screws and an incorrect P-lead spring that had seemingly been modified to fit.
- The advance-side timing was so misaligned that it couldn’t even be measured.
- Three of the nine ignition leads from the left-hand harness failed a continuity test.
This faulty ignition system meant the engine wasn’t getting the proper spark at the right time—leading to a partial power loss at a critical phase of flight.
The Human Element: Pilot Experience and Decision-Making
The pilot, a seasoned aviator with 1,820 total flight hours—665 of which were in this specific make and model—had a solid background in flying.
Just before takeoff, he performed a run up check. He increased the engine RPM’s to about 1800 and saw an RPM drop of about 75 to 100 RPM on the magneto check, which he described as normal for that airplane. He completed his full run up and re-stated that it sounded fine.
When the pilot recognized the engine malfunction he knew he was too low to the ground to troubleshoot so he made a split-second decision. Maintain aircraft control (aviate) and then look outside and find a suitable place to land (navigate). Although the NTSB didn’t mention it, I’m sure the pilot warned his passenger to brace for impact (communicate). If the pilot had prioritized looking inside and troubleshooting the problem, the outcome might have been far worse.
The Bigger Picture: Maintenance Matters
The aircraft had undergone a 100-hour inspection just nine months prior, in November 2022. That inspection reportedly included a magneto timing check, with no noted issues.
So, what went wrong? The investigation suggests that improper maintenance—potentially involving incorrect parts and loose components—set the stage for this failure.
This case is a stark reminder that even small errors in maintenance can lead to big consequences in flight. Pilots and mechanics alike must be diligent in ensuring aircraft systems, especially critical ones like ignition, are in proper working order.
Lessons Learned
- Aviate – Navigate – Communicate – Sometimes things go wrong and you won’t have time to troubleshoot the problem. Maintain aircraft control, analyze the situation and take the appropriate action, land as soon as conditions permit.
- Magnetos Matter – The ignition system must be meticulously maintained. Improperly serviced magnetos can cause partial or total power loss at the worst possible moment.
- Know Your Terrain – When departing from an airport with nearby elevation changes, be prepared for how terrain can impact climb performance, especially if a power issue arises.
Final Thoughts
The pilot and passenger were able to walk away from this accident unscathed because of how the pilot remained calm and handled the situation. This is a good reminder to never become too complacent – you don’t know when things might go wrong.
9 Comments
How would checking the RPM while the aircraft was climbing have altered the situation? One of the magnetos was faulty. The pilot couldn’t do anything about that from the cockpit.
I agree and I’m editing the blog to reflect that. In my initial review of this, the NTSB made a point to mention his lack of checking the RPM in their final report. The final report also did not mention any run-up check prior to the flight. I went back and reviewed the docket and found a statement from the pilot that said “he performed a run up check. He increased the engine RPM’s to about 1800 and saw an RPM drop of about 75 to 100 RPM on the magneto check, which he described as normal for that airplane. He completed his full run up and re-stated that it sounded fine”.
In this scenario, I think the NTSB should have said in their final report that when the engine lost power the pilot was focused on looking outside to find a suitable landing area rather than inside trying to determine what the RPM was doing. That was the right decision to make.
Howdy Hoover-
I love this new product. It provides just enough narrative detail of an incident, In order for us to get a decent ‘takeaway’ from it. The links to the NTSB dockets is also very helpful. I’ve found occasionally, that digging through NTSB files can be difficult. Hopefully, these can help in managing your time. You can get one of these posted ‘quick and dirty’ and then you can do a full report (or not) at your leisure.
I have a small home-based business restoring a particular vintage clock for sale or having a client ship me theirs for a repair and rebuild. I’ve found it’s very strange how orders seem to ebb and flow. I’ll have just a few over a month or less, THEN wammo, I’ll get 3 or 4 orders in a day or two, and immediately be behind trying to get them out in a timely manner. Based on how we’ll have very few incidents in aviation and then 3 or more, back to back. Putting you behind when trying to get a recording done. I just see some parallels.
As always thanks and fly safe –
Mark
Excellent debrief with lessons learned about always checking instruments, trust but verify maintenance, and knowing that luck isn’t something to be counted on.
Good thing the trees cushioned the crash!
Am very satisified that at times I get a mechanic’s “dander up”.
There is no substitute for paying attention to details like checking to make sure refuelers shut the refueling loading hatch. I always go behind the mechanics and baggage handlers and check how things are stowed. I at least observe, and at times feel, and test for tightness, or other situation I have had nothing to do with.
Always check someone else’s work. I don’t care if they get peeved…I’ve even had them replace a screw whose head was stripped. The tech had a hard time about removing the screw and did not like that I checked the size screw that was being used as replacement. Check everything every time as much as you can.
A couple of times I have found reason enough to not fly/delay take off. Going through checks works to keep aviating safe and enjoyable.
Sounds as if there were some shade tree mechanics involved as well. Good review and really like the format.
Great article and reminder. The airport I fly out of in Missouri, M48, has rough terrain in the north departure, scattered building and fields on the south departure, then rural area from there. I remind myself before each take off on what to do with what’s available in case I have an engine problem. Either departure direction, it’ll probably leave a scar but “aviate” and you’ll walk away from it.
This new layout looks good and works well.
As a lifelong car engine mechanic and amateur pilot, I think something’s wrong with the conclusion of the NTSB. Even the complete failure of one of the magnetos couldn’t cause such power loss. That’s why everything having to do with the ignition is doubled; two plugs, two sets oof ignition wires, two separate mags. His runup report isn’t honest, I suspect. One good magneto would provide plenty of power to remain airborne, which is the plan since the Wright Brothers first flew.
Here’s what happened. One of the magnetos wasn’t working at all well when he took off. But, dammit, he really wanted to fly that day, and he decided to gamble, since he wouldn’t have been able to get the problem fixed for days, at least.
I’ve always loved working with vintage cars and engines, which worked marvelously in their time. But age inevitably affects everything. Engines, like people, get
irritable and cranky. I know steam locomotive engineers who swear their engines have regular moods.
Gidday Hoover
Thank you for contributing such a valuable resource to our community.
Kind regards
Donald Payne
New Zealand