Tag Archives: Aviation Safety

Crazy video shows Delta Boeing 737 hit by lightning strike

A passenger has caught on video a direct lightning strike on a Delta Boeing 737 at Atlanta airport.

The video below is extremely interesting. Shot at Atlanta airport during a thunderstorm by Jack Perkins, a passenger of another plane, it shows a lightning strike hit a Delta Boeing 737 on the taxiway.

No one was hurt as a consequence of the lightning as the plane is shielded by Faraday Cage, that blocks out external static electrical fields: charges redistribute on the conducting material and don’t affect the cage’s interior.

In simple words: if hit by a lightning aircraft let the current pass through the fuselage until ground, preserving the systems’ integrity. Furthermore, all commercial and military aircraft have been designed to meet several safety lightning-related requirements needed to get the airworthiness certifications required.

Generally speaking, lightning strikes are rare and do not represent a real threat to military and civil planes, even though, in the 1980s, some F-16 Fighting Falcon jets were lost after being hit. In one case, the lightning ignited the vapors in the empty centerline tank, which exploded causing extended damage to the aircraft’s hydraulic system.

 

This video shows that weapons release from military planes can go horribly wrong

If you thought that just dropping an inert weapon during a test to validate a specific platform or procedure was an easy and safe task, you were wrong.

The following video shows a series of catastrophic incidents caused by a bomb release or tank jettison gone wrong.

Impressive.

Weapons separations involving new aircraft, pylons, tanks or ordnance are always filmed to evaluate and prevent incident like those shown in the video.

Weapons release gone wrong

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Scary video: This is the kind of landing you should be frightened of. Wingtip touches the runway during banked approach

On Jul. 18, 2012, a Boeing 737-200 operated by Sky Airline, sustained heavy damage to the right hand wing in an accident that occurred at La Serena – La Florida airport, in Chile.

The aircraft, flying as SKU-101 from Antofagasta, banked right while on final approach prior to touchdown and the right hand wing tip hit the ground.

The pilot aborted the landing, performed a go around and decided to divert to Copiapó – Chamonate Airport (where it safely landed) after assessing the damages: the wing tip was deflected upwards and even the flap was damaged.

If you wonder what the aborted landing scene looked like from a SKU-101’s passenger seat, here is the answer:

According to the reports, the weather was fairly good. The visibility on the ground was deteriorating but the runway visual range at the time of the (missed) approach was 6,000 m.

Tight circuits involving “banked finals” are often flown by airlifters, tankers and military/government planes and bizjets for training purposes, but I’ve never seen a civil liner (besides those landing at Kai Tak airport in Hong Kong) on a scheduled service banking so much prior to touchdown, even if some may be “crabbed” to fly the final approach under crosswinds (meaning that a WCA, Wind Correction Angle, is applied by aligning nose and tail with the wind direction while the aircraft is following a different course).

Moreover, based on the few available details, it’s really difficult to understand the reasons for such a curved approach although it seems enough safe to say that the crew opted for the go around a bit too late.

On Mar. 1, 2008, a Lufthansa Airbus 320 approaching runway 23 at Hamburg under strong crosswinds was invested by a gust right before touchdown that raised the right wing leading to an unstable flare. The left wingtip slided along the runway causing a wingtip and slat damage.

Photo: C-17 creates a huge cyclonic twist during NASA test

There’s a certain interest in technologies capable to detect volcanic ash in flight since, in April 2010, the European airspace was almost paralyzed as a consequence of the eruption of the volcano Eyjafsallajokull, in Iceland.

Many airports were closed and thousands commercial flights cancelled whereas, on Apr. 15, melted ash was found on the inside surfaces of some Finnish Air Force F-18 Hornets  involved in a training mission few hours before the imposition of airspace restriction caused by the huge ash cloud.

Volcanic ash is extremely dangerous for both propeller and jet aircraft: volcanic dust is extremely fine and can easily invade the spaces between rotating machinery and jam it; furthermore, the silica melts at about 1.100° C and fuses on to the turbine blades and nozzle guide vanes (another part of the turbine assembly) which in modern aircraft operate at 1.400° C, with catastrophic effects.

When a volcano erupts, training activities are postponed, exercises are cancelled or scaled-down, but security air traffic, such as air policing and Quick Reaction Alert (QRA) sorties must be flown. With some risks.

That’s why, as done by other companies and air forces, NASA has partnered with the U.S. Air Force and Pratt & Whitney to develop and test technology for improved sensors that can detect changes in vibration, speed, temperature and emissions which are symptomatic of engine glitches and can alert pilots to the presence of destructive volcanic ash particles, before the engine is damaged.

During one of these health monitoring tests, water was intentionally sucked by a U.S. Air Force C-17 (tail #87-0025) with the impressive results you can see in the image below.

Next step is to “inject” cereal and crayons in the engines: they will leave a colorful trail of grains and wax that can be studied to evaluate if the sensors work properly.

Image credit: NASA / Tony Landis

Video: Best or Craziest helicopter pilot in the world?

This might be the best or even the more dangerous helicopter show you’ve ever seen.

The video, most probably filmed years ago (based on the poor image quality), shows an Australian OH-58 Kiowa performing stunts inside what looks like a packed stadium, at low level around a man acting like a sort-of chopper tamer.

Such maneuvers require a lot of experience, skill, cold blod and insanity: the one piloting the chopper may have been the best pilot in the world or even the most daring. But he’s performing the display with zero safety margin: a simple error or a minor mechanical failure would mean the death of a lot of people.

On a side note, after the craziest helicopter show in the world, beginning at 04:00 minutes, you can see an interesting hoist recovery performed by a Royal Australian Navy Sea King (in the old color scheme).

Thanks to Ugo Crisponi for the heads up