One might think that a twin-engine aircraft is safer than a single-engine aircraft.  After all, if one engine fails, you still have the other to bring you home safely.  That’s the whole point of the second engine, right?

If one of the twin engines fails in cruise flight, maybe that’s true.  But if it quits right after takeoff, the twin can be extremely difficult to handle.  When the aircraft’s landing gear is down, its flaps set, and its airspeed just above the minimum flying speed, the asymetric thrust generated by the operating engine can flip the aircraft onto its back and out of control.  A "Vmc roll", as it is called, isContinue Reading Tesla Cessna 310 Crash at East Palo Alto: The Paradox of the Twin

Cirrus aircraft are now available with "flight into known icing" (FIKI) capability.  That’s a great feature. I’ve written before, however, that Cirrus is asking for trouble with its marketing.  Cirrus sells the feature as one that both enhances safety and increases the aircraft’s utility.  But Cirrus can’t have it both ways.  If a

Updated February 12:

A Cirrus SR-20 single engine aircraft collided with a Pawnee tow plane that was pulling a glider. The Cirrus reportedly ran into the Pawnee’s tow line. The Pawnee crashed and the pilot was killed.  The occupants of the Cirrus were also killed.  The glider pilot, however, recognized the impending collision, released his aircraft from the tow line, and landed without injury to himself or his two Continue Reading Cirrus – Pawnee Mid-Air Collison Near Boulder, Colorado

The FAA has instituted new rules designed to keep sightseeing helicopters from colliding with airplanes that are transitioning the Hudson River Corridor near the Statue of Liberty.  The San Francisco Daily Journal, California’s largest legal newspaper, published this column on how the new rules came to pass, and why they aren’t enough.

FAA and

The NTSB’s preliminary report on the crash contains little more than what was in the news accounts. The report does, however, offer one bit of new information.  The helicopter impacted on a magnetic heading of 230 degrees.  That heading is not in line with the route from Reno to Susanville.  While that might ultimately prove to be important, little can be made

Aircraft engine manufacturers recommend that owners overhaul their engines when they accumulate a certain amount of operating time, usually between 1200 and 2400 hours depending on the engine’s make and model. For example, Teledyne Continental Motors suggests that owners overhaul its IO-550 model engine at 2000 hours. Textron LycLycoming Engine - photo by wirelizardoming suggests that owners overhaul its O-235 engine, like the one pictured, at 2400 hours.

Overhauls are expensive.  Some can cost $40,000 or more.  An increasing number of owners opt to run their engines 200, 400 or more hours past the manufacturer’s recommended "time between overhauls," or TBO.  Once past TBO, they may take extra precautions by, for example, regularly sending out engine oil samples for spectrographic analysis, checking the engine’s compression, and looking inside certain parts of the engine with a boroscope to insure that  things look good. They feel the manufacturer’s TBO recommendations are somewhat arbitrary. By running their engines past TBO they are squeezing more life out of them, and that just makes good economic sense.

The FAA does not require private owners to comply with the manufacturer’s stated TBO interval. The manufacturer’s TBO is therefore advisory only.  As long as a properly certified mechanic hasContinue Reading Running Past TBO: Smart Economics or Owner Negligence?

Burdett v. Teledyne Continental Motors involved the forced landing of a Beech Bonanza after the Teledyne Continental IO-550 engine installed in the aircraft came apart in cruise flight. The passenger was severely injured.

The National Transportation Safety Board blamed the engine failure on the mechanic who last worked on the engine, and cleared the engine

An A-Star AS350B air ambulance helicopter crashed November 14 at Doyle, California, killing the A-Star Helicopter that Crashed Saturdaythree crew members on board.  According to an article in the Reno Gazette Journal, the pilot made a distress call before the crash. That indicates that the pilot was likely experiencing a mechanical emergency. The photographs accompanying the article show that the wreckage was spread over a fairly large area.  That indicates that the pilot lost control of the helicopter well before he was able to attempt an emergency landing.

Under the circumstances, the NTSB will be looking at the helicopter’s Continue Reading Mountain Lifeflight EMS Helicopter Crash at Doyle, California

Zodiac AircraftThis past April, the NTSB called upon the FAA to ground the entire fleet of Zodiac aircraft because their wings tend to fall off in mid-flight.  As it turns out, a defect in the Zodiac’s design induces an aerodynamic phenomenon known as flutter.  Flutter can destroy a wing or other control surface in a matter of seconds.