At least a half dozen Cirrus SR22T aircraft have lost power on takeoff and crashed. According to the National Transportation Board, in each case the aircraft pumped too much fuel to the engine, causing it to flood.  That remains ongoing danger. According to the National Transportation Safety Board:

 until the Federal Aviation Administration requires implementation of appropriate mitigating actions to prevent the loss of engine power due to excessive fuel flow in the SR22T, additional accidents may occur due to this hazard.” 

NTSB AIR-22-04

What’s going on?  Why do the SR22T engines flood?

The SR22T’s engine is the TSIO-550K engine, manufactured by Continental Motors.  Cirrus rigs the aircraft’s fuel system to pump up to that engine up to 42 gallons per hour.  But Continental Motors tested and certified the TSIO-550-K  engine to only 37.5 gallons per hour. That’s the limitation set forth in the engine’s installation manual and its type design data.  It’s no surprise then, that as Cirrus has the fuel system rigged, the TSIO-550-K engines tend to flood — Cirrus is operating the engines in excess of their certificated fuel flow limit.

The real question is whether, given that the fuel flows exceed the engine’s certificated maximum, the aircraft’s certification is even valid.

Each engine installed in an aircraft must have a valid type certificate issued by the FAA. (Federal Aviation Regulation 23.903(a).) If an engine is operated so that its fuel flows exceed its certificated limitations, then the type certificate is invalidated.  Without a valid engine certification, the aircraft cannot be certificated.  To be airworthy, an aircraft must have both a valid engine and a valid aircraft certificate. According to FAA guidance,

non-compliance with the engine manufacturer’s installation requirements can invalidate the type certification status of the engine, making the engine non-compliant with § 23.903(a)(1). This, in turn, would prevent certification of the airplane under part 23. Examples of engine requirements that could be affected by the airplane installation may include, but are not limited to, the following: 1. Fuel delivery flow and pressure requirements. . .”

(Federal Aviation Administration Advisory Circular AC-16A.)  

In order to legally operate the TSIO-550-K engine at the increased fuel flows, Cirrus might have applied for and obtained from the FAA a “supplemental type certificate” for the engine, approving the higher fuel flows upon a showing that the higher flows were safe. But it did not. Accordingly, as installed in the SR22T, the TSIO-550-K engine does not comply with Continental’s installation manual or the engine’s type design data. Under the FAA regulations, it would appear the aircraft does not have proper and valid certifications and thus is not airworthy.

Instrument approach procedures are pre-determined paths and maneuvers that, if followed, will guide an aircraft to a runway in reduced visibility.  The last leg of an instrument approach procedure is typically a straight line (more or less) to the end of the runway.  The straight line minimizes the turns the pilot must make to land the aircraft.

N880Z Crashes during Circles to Runway 27

Sometimes a pilot flies an instrument approach procedure but, just before landing the aircraft, turns the aircraft to land on a different, perpendicular runway.  Flying an instrument approach procedure to one runway and landing on another is called a “circling approach” or a “circle-to-land” maneuver.  A pilot might opt for a circling approach because the winds favor landing on the perpendicular runway, or the length of the perpendicular runway is more suitable to the aircraft.  To perform a circling approach, the weather must be good enough that, as the aircraft gets close to the airport, the pilot can actually see the runways and the surrounding environment.  Circling approaches are challenging maneuvers, especially in jets.  It is hard enough to circle close to the ground when visibility is good.  Harder still when visibility is restricted due to weather.  Proving the point, a Bombardier jet crashed a few months ago during a circling approach at Truckee.

Circling approaches are even more difficult at night.  Some pilots have a personal rule: No circling approaches at night. Those pilots will either land on the assigned runway, regardless of unfavorable winds, or proceed to a different airport.  Better safe than sorry.

But even those pilots might circle at night at his or her home airport.  That’s because the maneuver is easier if the pilot is familiar with the runway lighting, the surrounding lights, and the surrounding terrain. There’s less risk of getting disoriented.

Learjet N880Z operated as an air ambulance.  Last night it was making a short flight from John Wayne Airport to Gillespie, its home base, reportedly with four on board.  It appears it was a “repositioning flight.”  That is, the aircraft was not flying a medical transport mission, but rather was simply returning home. It was dark. The weather was marginal but certainly acceptable.  The pilot began the instrument approach to Runway 17.  The surface winds and the runway length made a landing on Runway 17 a straightforward affair.

As he approached the runway, the pilot decided to circle to land on the perpendicular runway.  It isn’t apparent why he decided to circle. Perhaps landing on the perpendicular runway would leave him with a shorter taxi to the aircraft’s hangar.

In any event, as the pilot began the circling maneuver, he asked the tower controller to turn up the runway lights.  His request indicates that, due to the reduced visibility, the pilot was having difficulty making out the runway lights.  The controller replied that the lights were already at 100% intensity. Shortly thereafter, as the pilot began his turn to line up with the perpendicular runway, the pilot lost control of the aircraft and crashed.

This type of accident is exactly why many pilots will not conduct a circling instrument approach at night.

Some media outlets have reported that poor visibility from the PG&E Dixie wildfire smoke may have caused the Bombardier Challenger jet crash in Truckee.   If true, would that make PG&E liable?

Probably not.

PG&E is liable to those whose property burned in the Dixie Fire, or those whose property was damaged by smoke from the fire.  That’s because California’s inverse condemnation doctrine essentially makes PG&E  automatically liable for property damage claims resulting from fires that its equipment sparks.  Further, PG&E may be liable to affected property owners for things like emotional distress under the legal doctrine of “Trespass by Fire.”  Finally, PG&E would be liable for personal injuries or death resulting from the fire if the individual proves that the Dixie Fire was the result of PG&E’s negligence.  That is, one injured by the Dixie Fire or its smoke can hold PG&E accountable if the Dixie Fire was the result of PG&E’s lack of due care in operating its facilities or in keeping the trees around its powerlines property trimmed.

Assuming for argument’s sake that the smoke for the fire contributed to the crash, it’s still unlikely PG&E can be held liable.  The doctrine of inverse condemnation applies only to property damage claims, not to personal injury or death resulting from fires. The doctrine of Trespass by Fire applies only to injury suffered as a result of fire coming onto property owned or occupied by the one injured.  So that wouldn’t apply either.

That leaves the doctrine of negligence. Assuming PG&E caused the Dixie Fire, and further assuming PG&E’s conduct that caused the fire was negligent, it still wouldn’t be enough.  To recover on a negligence claim, the family members would also have to prove that PG&E had a “duty” to not subject their loved ones to the type of risk that PG&E’s conduct exposed them to.  The concept of legal duty is tricky.  Certainly, PG&E had a duty to those whose homes were burned because it was reasonably foreseeable that if it started a fire, property damage would result.  But it’s a stretch to say that PG&E should have foreseen that smoke from a fire would reduce visibility for flights in the area and could contribute to a plane crash.  Because such harm was not a “foreseeable” risk of igniting a fire, it’s unlikely a court would hold PG&E liable.

PG&E’s liability for Dixie Fire claims is most likely limited to property damage and injuries it’s fire caused on the ground.

Few turns in aviation are as dangerous as the “base-to-final” turn.  That’s the last turn the pilot executes to line up with the runway.

When that final turn is made, the aircraft is always low and slow. If the pilot tightens the turn too much, the aircraft can stall and crash.  The factors that contribute to a base-to-final crash include:

  • The pilot carrying too much speed, thus requiring a tighter turn so as not to overshoot the runway centerline;
  • A tail wind requiring a tighter turn so as not to overshoot the runway centerline;
  • The aircraft being low in the turn, leading the pilot to compensate by pulling the nose up;
  • High density altitude conditions which result in an indicated airspeed yielding a higher groundspeed than normal;
  • High density altitude conditions which results in decreased aircraft performance.

It’s of course too early to tell why the Challenger N605TR crashed at Truckee.  But the accident has all the earmarks of a base-to-final stall/spin.  All of the above-listed contributing factors may have been at play, making the base-to-final turn especially hazardous for the crew. And witnesses report seeing the aircraft in an extreme left wing down attitude shortly before impact – just as is typical in these sorts of accidents..

All too frequently, smaller general aviation aircraft fall victim to the base-to-final stall/spin . But large jet aircraft like the Challenger typically avoid the risk by lining up with the runway centerline while still miles away from the airport. Because large jets cannot fly slow, and because jet engines respond to throttle inputs relatively slowly, jets such as the Bombardier Challenger are ill-suited for tight maneuvering flight low to the ground near landing speeds.

Seems as though in attempting to maneuver to the runway, these pilots had the deck stacked against them.

The animation below syncs ATC communications with the aircraft’s flight path.

Challenger 605 crashes during approach at Truckee/Tahoe, CA – YouTube

At first glance, this week’s crash of Cirrus N89423 at Truckee looks like yet another “high density altitude” accident.  Such accidents are, after all, perhaps the most common type of accident at Truckee airport.  Due to the thin air, the aircraft cannot climb fast enough to clear rising terrain or to maintain altitude in

Accident Aircraft

downdrafts.  Sometimes the climb performance might be adequate but the pilot, growing impatient, asks more of the aircraft than it can then provide, usually with lethal results.

Certainly, this accident has many of the earmarks of the typical high-density altitude crash:

  • Truckee is at altitude – 5890 feet.
  • The weather was warm, meaning the air was even thinner thus further degrading climb performance.
  • Breezy conditions were conducive to generating downdrafts on the lee side of the surrounding terrain.
  • The Cirrus SR20 is of low horsepower for its weight and thus has little climb performance to spare

But there seems to be more to it than that.  High density altitude accidents often catch those who are unfamiliar with high density altitude operations, or at least are unfamiliar with the terrain surrounding an airport.  When the pilot asks of the aircraft more climb performance than the aircraft can deliver, the aircraft gets too slow to continue flying, the wing stalls, and the aircraft crashes.

N89423 flight path

But this was an instructional flight.  The flight school, Mountain Lion Aviation, was based at Truckee airport.  The school boasts experience in Cirrus aircraft and so, presumably, the instructor was well familiar with the modest climb performance capabilities of the Cirrus Sr20 and familiar with the airport, the surrounding terrain, and the effects of high density altitude as they then existed.  Further, per the air traffic control tapes, the plan was not to depart the area, but rather stay within the relative safety of the traffic pattern.

Definitely not the usual “high density altitude” accident profile.

In May, a Piper Navajo PA-31 crashed shortly after takeoff from Myrtle Beach.  The pilot was ATP-rated and worked for American Airlines.  He knew he was in trouble almost immediately after takeoff.  He tried to return to the airport.  He reached an altitude of about 1000 feet, then dropped 475 feet, then climbed 700 feet, then dropped off radar at 450 feet.  The pilot was killed in the crash.

The NTSB now says the aircraft had just come out of an annual inspection.  The control surfaces had been removed and repainted during the annual. It appears that the aircraft’s trim tabs were installed upside down and backward. That would make the aircraft largely uncontrollable.  Once the aircraft was in the air and building speed, the more the pilot attempted to get the aircraft’s nose to point up, the more it would point down.  And vice versa.

As unthinkable as the maintenance error would seem, it is not uncommon.  Many aircraft have crashed after maintenance because aircraft trim mechanisms were installed incorrectly.  The outcome is usually fatal.  But below is the story of one that ended in a safe landing.  It’s instructive from  the perspective of both the pilot and the mechanic.

When you read about these accidents, you are sometimes left wondering why the pilot could not figure out that his controls were reversed and proceed accordingly.  The pilot in the story below explains.  Then the mechanic responsible for the misrigging explains how he had heard stories of crashes that resulted from a mechanic misrigging elevator trim tabs, and that he was sure he would never make such an unforgiveable mistake.  And yet he did.



Among the most dangerous  activities in the aviation industry is the installation on an aircraft of unapproved or bogus parts – parts that have not been properly tested, approved, and certified as safe.  The practice has been linked to the crash of both commercial and private aircraft.  It is illegal to install uncertified parts on an aircraft and the practice is so dangerous that those who do can end up in jail.

The FAA has now determined that Boeing installed unapproved parts on over 700 of its 737 aircraft.   We’re not talking here about parts related to the crash of the two 737 Maxes.  These unapproved parts relate to the 737’s navigation system and are an entirely different scandal.

As a result of catching Boeing — once again red-handed – knowingly rolling the dice with the safety of the flying public, the FAA fined Boeing.  That’s good.  According to FAA administrator Steve Dickson:

Keeping the flying public safe is our primary responsibility.  That is not negotiable, and the FAA will hold Boeing and the aviation industry accountable to keep our skies safe.

But the fine was only $17 million.  For Boeing, that’s a pittance.  It’s likely that by installing the unapproved parts and paying the fine, Boeing is dollars ahead from where it would have been had it stopped production of the aircraft and awaited parts that were properly certified.  It’s hard to see how the FAA’s action will deter Boeing from taking future safety shortcuts.  In fact, it seems that the FAA is giving Boeing a pass.

Families of those lost in the Ethiopian Airlines Boeing 737 Max crash met with Biden’s Transportation Department seeking to get the top FAA official fired for being “too cozy” with Boeing. According to the families, “The FAA has been, and continues to be, more interested in protecting Boeing and the aviation industry than safety.”  The families specifically question why the FAA did not ground the Max jets after the crash of the first 737 Max crash in Indonesia.

The problem, however, is  not just the FAA leadership.  Rather it’s the entire FAA system that needs to be overhauled.  It is now a mere shell of what it once was.  Indeed, it was 10 years ago that the FAA abdicated to Boeing its certification responsibilities and granted Boeing the power to certify its own products. I questioned then whether that was in the best interests of safety.

Beginning August 31, the FAA will allow Boeing to self-certify its designs. The FAA will not even do the rubber stamping — Boeing employees will do that too. According to the Seattle Times, “the new system increases the authority of the in-house inspectors directly managed by Boeing, allowing them to review new designs, oversee testing to ensure the products meet all applicable standards, and sign off on certification.”

Allowing Boeing to “self-certify” seemed like an obviously bad idea at the time.  It wasn’t long thereafter that that Boeing’s new 787s began to catch fire.  The NTSB investigated, and raised the same concerns that I had a few years earlier. NTSB Chair Deborah Hersman hinted that maybe, just maybe, the FAA isn’t doing its job:

This is an issue when you have a regulator with limited resources. . .You can delegate some of the action, but you can’t delegate responsibility.”

The FAA didn’t listen.  Instead,  it allowed manufacturers to certify even more of their own products. In fact, by 2017, the FAA outsourced 90% of all aircraft certification work to the manufacturers themselves.

The FAA no longer oversees the manufacturers.  It is not longer staffed for it.  It is no longer funded for it.  Firing a few FAA officials won’t fix the problem.

On October 2, 2019, a World War II-era B-17 flying fortress bomber departed Bradley International Airport in Connecticut for a local sightseeing flight with 10 paying tourists on board.  Shortly after takeoff  the pilot radioed that he was returning to the airport because of an engine problem.  A witness reported an engine was sputtering and smoking. Ultimately, the pilot reported a problem with yet another of the aircraft’s engines. The airplane crashed on the airport premises and burst into flames.

Seven occupants were killed. Two persons on the ground were injured.

(This figure shows the airplane’s flightpath on Oct. 2, 2019, between 9:46 a.m., when the airplane was cleared for takeoff, and 9:51 a.m., when one of the pilots reported the airplane was at midfield. The locations when the airplane reached 400, 300, and 150 feet above ground level are also shown.)

The four-engine bomber should have been able to make it to the field with the engines that remained operational.  But the landing gear was extended prematurely, and the added drag was too much for the aircraft to overcome. It hit the runway approach lights and crashed.

The aircraft was owned by the Collings Foundation.  The pilot served as the Foundation’s director of maintenance. The NTSB found that two of the aircraft’s four engines failed to develop full power, and that the loss of power was due to the pilot’s inadequate maintenance. The NTSB also determined that the Collings Foundation’s safety management system was ineffective and failed to identify and mitigate numerous hazards, including those related to the pilot’s improper maintenance of the vintage aircraft.

Most folks who pay to get into an aircraft for a ride assume that if the aircraft or the operation was unsafe, the FAA would not allow it to fly. But the NTSB found that the FAA’s oversight was lacking as well.  In essence, the FAA failed to protect the public from a shoddy operator.

Download the NTSB’s report, just released, here.


The pilot of a Bellanca 8GCBC Scout, Registration N4116Y, died when the aircraft crashed at Byron Airport on May 9th.  According to a witness, the tow plane took off pulling a glider. While still at a low altitude, the glider climbed abruptly.  The maneuver pulled the tail of the tow plane into the air, pointing its nose down.  “The tow plane cut the cord and tried to recover but it was too late.” The tow plane crashed onto the runway and caught fire.

Bellanca 8GCBC Scout at Byron
Accident Aircraft Prepares for Glider Tow

This particular accident profile is not uncommon.  That’s why it is the responsibility of the glider pilot who is being towed to keep the tow plane in sight at all times.  If the glider pilot climbs abruptly and, as a result, loses sight of the tow plane below, it’s the glider pilot’s responsibility to release the tow rope so this sort of accident does not happen. 

According to the FAA Glider Flying Handbook:

One of the most dangerous occurrences during aerotow is allowing the glider to fly high above and losing sight of the towplane. The tension on the towline caused by the glider pulls the towplane tail up, lowering its nose. If the glider continues to rise, pulling the towplane tail higher, the tow pilot may not be able to raise the nose. Ultimately, the tow pilot may run out of up elevator authority. . . Upon losing sight of the towplane, the glider pilot must release immediately.

The tow plane belonged to the Northern California Soaring Association.   According to another witness report, just before the glider zoomed up and forced down the nose of the tow plane, the glider’s canopy opened for reasons unknown.