Date of accident: 03.04.99

Time of accident: 0800Z

Aircraft registration: ZS-WLI

Type of aircraft: Bellanca Citabria 7ECA

Licence type: PPL

Pilot-in-command flying experience: Total flying hours: 511

Hours on type: 55

Type of operation: Private

Last point of departure: Brits (FABS) near Pretoria

Next point of intended landing: Klerksdorp (near Johannesburg)

Location of the accident site: Klerksdorp

Meteorological information: CAVOK

No. of people on board: 1 + 1

No. of people injured: 0

No. of people killed: 0

1.1.1: The pilot and his passenger departed Brits Aerodrome at 0430Z for a private flight to Klerksdorp Aerodrome. The purpose of the visit was to attend the Experimental Aircraft Association (EAA) Annual Convention.

1.1.2: The following is a description of the accident by the pilot: “The ATC changed the circuit from 360° to 180° due to an aircraft blocking the active runway. There were about nine aircraft in the circuit, which caused us to land close behind each other”.

1.1.3: “I landed on Runway 18 with a 10-12kt tailwind, at about 45mph the aircraft ran off to the left of the runway. I could not apply power due to other aircraft ahead of me, and tried to correct with rudder and brakes. I was unable to avoid a ground-loop”.

The pilot lost directional control after landing and was unable to prevent the ground-loop.

Jim’s analysis
Oh dear, oh dear, oh dear. We have a 500 hour pilot with the mentality of a sheep. Okay, I’m being unkind. I’m sure he is a hell of a nice guy, but folks, this is what being a pilot is all about. Making intelligent decisions and exercising command-ability.

Actually, the pilot was under a lot of pressure. There were a hell of a lot of aircraft around, many of them would have been his mates and everyone else is landing safely so he is going to feel a right berk if he’s the only one to chicken out. It is serious pressure, but the pressure didn’t cause the accident – the pilot did by allowing himself to be influenced by imaginary outside coercion.

If there had been no other traffic and no ATC would he have landed with a tailwind? I think not – he crashed his shiny aeroplane because he allowed himself to be pressured by ATC and the other traffic. He didn’t have the guts to say, “The rest of you are behaving like idiots, I’m out of here until things quieten down”.

And surely if you are too close to the traffic ahead, that in itself should tell you to do a go-around. The intelligent thing to do would have been to tell ATC you can’t accept the tailwind and you will be holding outside the circuit until they can accommodate you on the into-wind runway. Most of the time you can steer clear of accidents by sitting back and taking your time to make good decisions.

In any case it’s dumb to land a taildragger, or anything else, with a 20km/hr wind from behind. It means you’re landing 40km/hr faster than necessary. (I get this by comparing it to his landing speed into wind.) That 40km/hr on it’s own is enough to kill you if you come to a sudden stop. And we’re not talking about 40km/hr, we’re talking about 40km/hr on top of your proper touchdown speed.

His little Citabria normally lands at about 45kts, so if he landed into wind that day he would have had a groundspeed of 34kts (using 11kts as the average wind). But a downwind landing would’ve been at 56kts. So it’s 65km/hr against 105km/hr!

But we’re not finished yet. The rudder steers a taildragger on the ground, but for it to work properly the wind must come from the front. As the aeroplane slows down the rudder gets less effective and eventually starts working in reverse – right rudder turns you left. So the groundloop was not surprising.

What can we learn?
• Make your own decisions.

• Make your decisions early – it saves last minute panic.

•  Don’t let your passengers, or ATC, or your boss, or anyone, persuade you to make a decision that you are not comfortable with.

• A tailwind, even a slight one, can have very serious consequences on both take-off and landing.

Jim Davis has 15,000 hours of immensely varied flying experience, including 10,000 hours civil and military flying instruction. He is an established author, his current projects being an instructors’ manual and a collection of Air Accident analyses, called ‘Choose not to Crash’.

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