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737 aborts midlanding in extreme wind

enter air boeing 737 salzberg austria

Tense moments leading up to a tricky approach and landing at Salzberg airport in Austria on October 29.

The Polish Enter Air Boeing 737, arriving from Frankfurt, is on approach very gusty winds and highly technical crosswind conditions and unable to make a smooth touchdown following a storm. The storm, called Storm Herwart, had just passed through the area and caused severe weather in Germany and Poland this week.  

The 737 makes a highly technical approach through what look like severe gusty crosswinds, putting the plane in a crab at first, and straightening it out on short final. The crew of this Polish airline was attempting to land on 9000 foot long runway 33, with with winds reported at 270 at 26 gusting 46. The crosswind component was at 60 degrees. After a circling approach, a wind gust nearly drove the wing into the ground. 

The plane bounced off the runway as a strong gust caused the right wing to drop, and looks like at this moment, the pilots decide to overshoot, and initiate take off right away.

Another attempt at landing was not made, and the Boeing headed back to Frankfurt. This looks like the airplane narrowly averted disaster. Two airplanes behind the Boeing decided to go around after receiving the wind shear alert on short final. 

 

This must have been a scary and intense experience especially for the passengers. Amazingly, the approach was filmed by one of the passenger, which makes for some really interesting footage. It’s interesting to see it from this perspective as well. You can really get a sense of how hard the touchdown was, and the imminent overshoot. The video was shot by passenger Manfred Ortel. 

 

https://youtu.be/FUBtvy3Xssc

The Boeing returned to Salzberg in about an hour and landed without incident. 

Read more about crosswind landings here and see more videos about difficult crosswind landings

 

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How does Centre of Gravity affect your airplanes performance?

When you complete your weight and balance form every time before you fly, you need to make sure it fits into your weight and balance envelope. We’re all used to doing it, so it’s second nature by the time we’re licensed, flying for fun, or continuing our training. We’ve all been through this in ground school, but it’s important to refresh the knowledge and remember how exactly airplane performance and handling are affected as to where your airplane’s centre of gravity lies. 

Forward vs. Aft Centre of Gravity

Your airplane is designed with a certain centre of gravity and a small allowance within which it is acceptable to move it. By moving the C of G location, you are changing the amount of downward tail force and lift of your airplane. When lift is created, so is drag, and this causes a decrease in performance.  The airplane needs to be within the envelope to properly handle and retain tested stall characteristics.

What is balance?

Balancing an airplane is a lot like balancing a teeter-totter. For the aircraft to be properly balanced, the sum of all the moments to the left and right of the pivot point (or fulcrum) must be equal.  The fulcrum of the airplane is located at the centre of pressure – or Centre of Lift on the wing. 

weight and balance pilottraining.ca
The centre of lift and fulcum of your airplane, showing C of G limits. Image from pilottraining.ca.

The load on the left is the total weight of the aircraft located at the C of G which is balanced on the right by the elevators. So what if the C of G changes? The elevator force must also change. So must it change if the centre of lift (centre of pressure) changes.

Every aircraft has a certain maximum forward and rearward C of G limit. This is inherent in the airplanes initial design. 

Aircraft moment causes your nose to pitch down, the tail down force causes moment in the opposite direction, balancing the airplane. The tail is essentially an upside down wing that generates downward lift. The amount of lift needed depends on two factors, the location of C of G, and the weight of the airplane. 

Effects of tail heavy CG

When the C of G is rearward, elevators must produce less downward force to maintain level flight, so the aircraft will fly more nose low.  

The effects of this are poor longitudinal stability, reduced capacity to recover from stalls and spins,  and creates a situation where very light control forces and make it easier for the pilot to over stress the aircraft with smaller deflections. It also causes an increase in cruise speed. 

These effects stem from less tail pressure on the stabilizer. Stall recovery will be difficult, and in some cases impossible, because of less tail pressure. Have you ever noticed that you’re not allowed to have passengers is some small airplanes when practicing stalls and spins? The extra rearward C of G causes the airplane to be out of the utility category, which is required for stall and spin practice. The Cessna 172’s we train on are like that. A rearward C of G changes the flight characteristics enough to make upset recovery difficult.

Effects of nose heavy CG

When the C of G forward, this causes the airplane to nose down, and a higher angle of attack will be required to balance out the forces. The elevator, which is in the aft end provides a counter balancing force to the nose down attitude. 

The airplane will need nose up trim, will be more stable and will cruise slower.  This is because there is more pressure and drag from the stabilizer. 

Overloading

Since we’re talking about how to put weight in the airplane, take note to why overloading an airplane is not recommended under any circumstance.  An airplane that is overloaded is dangerous. A decrease in performance will be one problem you will see, especially initially, but also you’ll have to deal with:

  • higher speed needed for take off
  • longer distance required for take off
  • reduced rate of climb
  • decreased range of flight
  • lower cruising speed
  • reduced maneuverability of aircraft
  • higher stalling speed
  • higher approach and landing speed will be required
  • and a longer landing roll and stopping distance.

You may have seen dramatization in movies of what airplanes can do, often with great exaggeration.  If you’ve seen American Made, starring Tom Cruise, you’ll note the scene where the pilot is coerced to take off from a high altitude, hot, humid dirt strip in the jungle, oh and did I mention it’s also a short field “runway” with high jungle on both sides, and the airplane is overloaded? If you study aviation, you’ll know that this is a bit of a ridiculous scenario, and when the pilot (Cruise) barely makes it over the trees, clipping the tops of the large trees, he averted disaster, but the scene is incredibly exaggerated and completely unrealistic.  High altitude with obstacles (such as trees or mountains) makes take off very dangerous.

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The dangers of flying through rotor wash

We all know wake turbulence can be very dangerous, and this video shows that helicopter rotor wash is no exception.

Wake turbulence is invisible, extremely powerful and can last for several minutes, making it important to take note where the turbulence likely is, and time until it’s likely dissipated, or plan to fly over it instead of through it.

In this video, a UH-60 Blackhawk helicopter takes off, and only 27 seconds later, a Cirrus SR-20 attempts to land. The airplane appears to fly into the area where rotor wash was produced with disastrous results.

This accident happened in Fort Collins, Colorado. It’s reported that the pilot was only on his second solo in the Cirrus, and attempted to land long after he saw the helicopter take off. The rotor wash the airplane flew into put the plane into a steep left bank which was impossible to recover from since it was only a few feet from the ground.   

How helicopters produce rotor wash

Helicopters produce rotor wash much in the same way that fixed wing aircraft produce wake turbulence. The lift produced by the rotors create vortices that swirl downward, bounce off the ground and go up again. If winds are light, as they were in this scenario, the turbulence will linger a lot longer. In this situation, the pilot of the Cirrus hits the turbulence 27 seconds after the helicopter took off.    

On takeoff, rotor wash is harder to manage. If the pilot was taking off, the pilot would have to plan to have taken off well beyond the point where rotor wash is suspected, and to have climbed enough to avoid it, much like an obstacle take off

How to avoid rotor wash

Again, these procedures are similar to avoiding wake turbulence. Stay above rotor wash, know the direction the wash will travel due to winds. Stay upwind of the wash and give it several minutes to fully dissipate. Stay above and land beyond where the turbulence is. In this situation, the pilot should have either have tried to land long or just execute a overshoot.

In a controlled airport, air traffic control will help you avoid the wash, but if you’re in an uncontrolled aerodrome, you’ll have to be extra vigilant. 

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Space Shuttle launch and landing

This amazing footage shows the launch of the last space shuttle, the Atlantis, the last space shuttle to fly and marks the completion of the Space Shuttle program. The shuttle was launched from the Kennedy Space Center in Florida on July 8 2011.  The space shuttle is now retired. Different vehicles are now used to access space, including the Russian capsule Soyuz and the Orion. More vehicles are being considered and being tested.

The footage of this space shuttle  is very cool and shows some key phases during a mission, the launch, docking, approach and landing. As an extra bonus, it’s set to some pretty cool music. Make sure you have the music up for this video.

Have you ever wondered how the space shuttle comes back to earth? After approaching through atmosphere, the shuttle was flown very much like an airplane, with some pretty major differences in scale. The shuttle, with a heavy, rectangular body, huge nose cone and shorty, stubby wings is not very aerodynamic and essentially drops like a brick on approach. It takes roughly 3 and a half minutes to descent from 37,000 feet at a descent rate of 10,000 feet per minute. 

A flying brick

A typical descent path for an airliner is 3 degrees, but the shuttle is so heavy and produces so much drag, they use a 20 degree glide slope flown at 345 miles per hour with a descent rate of 10,000 feet per minute. To give you the immense difference of scale, a typical airliner will use a descent rate of 750 feet per minute flown at about 165 miles per hour. 

The shuttle touches down at around 200 knots (225 miles per hour), faster than the flown speed on descent of an airliner. 

In fact, NASA astronauts train in a modified Gulfstream II jet which simulates how unaerodynamic the space shuttle actually is. It flies with it’s landing gear down and engines in reverse. 

The landing gear doesn’t even go down until 300 feet before touchdown! The pilots only have one shot at landing; there is no fuel or power for a go around. The landing is simply a forced approach.

How exactly does the shuttle approach earth?

Interested in more information about the approach and landing? This video explains it really well, and is very entertaining. I’ve enjoyed watching this one a few times. Enjoy!

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High Speed Slalom Flying Through Wind Farm

High speed slalom flying through wind farm

Aerobatic pilot Hannes Arch flies an impressive obstacle course through a wind farm in Austria. Red Bull Air Race pilot flew this course in Tauern wind park in Oberzeiring, Austria.

This stunt is more dangerous than most Red Bull obstacle courses for many reasons. First of all, the pylons at the Red Bull courses are inflatable, so the airplane can hit them without suffering damage. However, clipping one of these turbine blades would have devastating consequences. These windmills are also taller than the Red Bull pylons, standing at 60 meters tall (230 feet). An additional challenge was that the terrain the windmills were built on is not even and situated on a ridge that is far from perfectly flat.

He was flying this course exceptionally fast, at 152 knots (280 km/h) and pulling 5.5 G’s in the turn.

The video shows adrenaline-rich flying footage.

The airplane is an Edge 540 V3. Read about Hannes Arch here.

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Watch the Giant Antonov An-225 Mriya land

Antonov An- 225 Mriya at the Farnborough air show in 1990. Image from Wikipedia.

The An-225 is a strategic cargo airlift aircraft powered by six turbofan engines.  It’s the longest and heaviest aircraft ever built, and first flew in 1988. There is only one of these airplanes in the world, only one was ever built. It holds the world record for single item airlifted payload at 189,980 kilograms (418,834 pounds). This made an airlifted total payload of 253,820 kilograms (545,000 pounds). In fact, it’s maximum takeoff weight is 640,000 kilograms – that’s almost 1.5 million pounds.

The name, Mriya, means “dream” in Ukranian.

Watch this aircraft land at Doncaster airport.

What is more impressive, the aircraft landing or taking off? On take off, this enormous aircraft’s six engines are screaming at full power, making some impressive noise, and showing what it takes to get this heavy airplane off the ground.

Now watch it take off from runway 16 at ZRH, Zurich, Switzerland in 2013.