Jim Davis – Aircraft Accident Report  

Jim Davis.

This discussion is to promote safety and not to establish liability.

CAA’s report contains padding and repetition, so in the interest of clarity, I have paraphrased extensively.

Aircraft registration: ZS-EIV

Date and time of accident: 3 May 1999 0445Z

Type of aircraft: PA28-180

Type of operation: Private

PIC license type: PPL

License valid: Yes

PIC age: 34

PIC total hours: 253.25

PIC hours on type: 160.20

Last point of departure: Grand Central Airport

Next point of intended landing: Saso lburg

Location of accident site: Apron at Grand Central Airport

Meteorological information: Wx fine

POB: 1+0

People injured: 0

People killed: 0

Synopsis:

The pilot prepared to fly, but when he attempted to start the engine, the starter motor was unserviceable. He reverted to starting the engine by hand swinging the propeller. The aircraft park brake was not applied and no chocks were used.

When the engine started the aircraft began to roll, the pilot attempted to board the aircraft but slipped and fell. The aircraft ran for about 100m and collided with a parked aircraft.

Probable cause:

The pilot neither used chocks nor did he apply the parking brake when he hand started the engine.

JIM’S COMMENTS

It keeps happening, doesn’t it?

A guy of 34 with 253 hours – most of which were on type, could not have got this far in his flying career without knowing that for prop-swinging you need a ‘responsible person’ at the controls, and the brakes should be on (or chocks in position).

Even if he didn’t know it, it’s just common sense, isn’t it?

I’m going to stick my neck out and say this guy was very familiar with the procedure – and that he had probably done it many times.

If he had never done it before surely he would have been super cautious.

Wrong – do not curl your fingers over the trailing edge.

This was a 60 year old aeroplane and the report says; ‘the starter motor was unserviceable’. Really, who diagnosed the problem? It’s much more likely to have been a flat battery caused by leaving the master switch on overnight. Or by battling to start on a cold winter morning.

‘familiarity breeding contempt’

This accident has all the signs of familiarity breeding contempt.

It happened to a very good friend of mine recently. Actually ‘happened to’ is the wrong expression – he ‘made it happen.’

And what’s my friend’s experience? He is not only a commercial pilot – he is a Grade ll instructor. Not only that, but he owns several vintage tailwheel aircraft that need to have their props swung every time he flies them. This means that not only does he know how to do it properly – he actually teaches prop-swinging.

I can feel his cheeks burning with embarrassment from here and he lives a thousand miles away!

He tells me, in mitigation that (a) he hadn’t had anything to eat or drink that morning, and (b) someone had bent the throttle slightly so that it didn’t close properly unless you gave it a good tug.

So, three lessons:

• It’s important to keep well hydrated.

• There’s a reason why air forces insist you eat before flying in the morning.

• Always, give the throttle a firm tug when you think it’s closed. Throttles are inclined

to be sticky at the beginning of their travel because they are seldom there – they normally operate much further forward.

So, what has this got to do with you, dear parishioner? Well, it depends who you are.

If you are a bold, confident member of the congregation, it may teach you not to bugger around with things you don’t understand.

‘I am a prop-swinger.’

And to the meek and timid, I beseech you to embrace the faith and, with due counselling, to move forward until you can be proud to say ‘I am a prop-swinger.’ It’s a step towards being a more proficient pilot – like flying a taildragger.

Let me tell you a story.

Twenty years ago I had a little flying business based at Jandakot airport at Perth. I was granted office space at a well-run flying school in exchange for me keeping a fatherly eye on half a dozen young instructors. I would help them with their briefings and lectures and offer a word or two on how to deal with problem pupes.

It was a happy and informal arrangement.

I got on well with Chuck, the all-American boss of the place. The only blot on the landscape was the 35 year old CFI. He was friendly enough, but he could see his young instructors regarded me as a mentor and this detracted somewhat from his previous top-of the-dung-heap status.

One day I decided to teach the instructors how to swing a prop.

Most of them were young, and all were enthusiastic. And they were soon thrilled to find that they could indeed hand start the company’s Cardinal – which was the aircraft we were practicing on. We were doing this on the apron in front of the school’s massive glass windows. So the CFI was able to witness our activity. Chuck wasn’t around. Anyhow when he returned, he had a yabber with the CFI and then told me that they didn’t approve because it was dangerous. I had to desist forthwith. Fair enough.

Fast forward two weeks and the CFI takes the company’s Seneca on an overnight charter a thousand miles north to some gawd-awful dump in the desert. Perhaps it was Kevin Bloody Wilson’s home town of Kickacoonalong.

Unfortunately, the next day, when the flight was due to return, the aircraft had a flat battery, and the CFI was the only company pilot who did not know how to swing a prop.

Chuck spent the next week bitching about how much it cost to fly an AME up there with a new, fully charged battery. I’m sure you get the drift of this sad story.

I could teach you to swing a prop on the internet – but I am not going to try. What I will do is give you the ground rules so that when you find a competent instructor the whole thing is pretty clear in your mind.

Okay, so here’s the low-down on how to swing a prop for starting the engine. Don’t try it until an experienced swinger has given you some dual.

Dress properly. Take off ties, caps, rings, watches, jackets and sunnies. Then roll up your sleeves and take your phone, or anything else out of your shirt pocket. We don’t want anything to drop out and distract you.

Stand on firm, dry ground, with shoes that are not slippery. Also make sure there is nothing behind you, like chocks, that you could fall over when you step back. Obviously do not chock a wheel that is immediately behind the prop.

You put your hand flat on the blade (see photo). Curling your fingers round (see other photo) can cause much pain and swearing if she kicks back.

How to grip a prop blade to swing it.

The swinger is in charge of the operation. Here’s what happens:

Swinger says          Pilot’s Action                                   Pilot replies

Brakes on.                 Checks that the brakes are on.     Brakes on.

Engine primed.         Checks the fuel is ON, the             Engine primed.

                                mixture is rich, and the engine is

                                primed.

Throttle set.               Sets the throttle.                             Throttle set.

Left mag, contact.     Switches on the left mag.               Left mag, contact.

Swinger pulls prop through compression and steps back in one smooth motion.

If the engine doesn’t start:

Mags off.                    Switches the mags off.                   Mags off.

The swinger re-positions the prop, then goes through the above sequence again.

When the engine starts, the pilot must remember to switch to both mags.

Take Home Stuff:

Seven Golden Rules for Turning a prop at ANY time:

1. Always expect a prop to be live. Turning it, even a fraction, may kill you. It happened recently at Windhoek.

2. Have the mixture lean, the throttle closed and the brakes on. It might still start, but it will only run for a couple of seconds.

3. Make sure the mags are OFF. This doesn’t guarantee safety, but it stacks the odds in your favour. Even with the key out the mags can still be live. You can sometimes remove the key in one of the ON positions. There have been several ADs (Airworthiness Directives) about this.

4. Don’t curl your fingers round the prop. If it backfires it will pull them off.

5. Don’t turn a prop backwards. This can damage the vacuum pump.

6. Don’t try prop swinging without dual instruction.

7. Dead-cut checks are critical. Do these after start-up, and before shutdown.