old man emu

Any auditors who approach an audit with such an attitude should be paraded before a classroom full of trainee auditors and have their pencils removed and broken before their very eyes. Then their clipboards should be snapped in half and hurled into the nearest garbage tin. Audits are not a means to gather evidence for prosecutions. They are a means to identify where improvements can be made in the areas being audited.

Unusually for me, I think this discussion is drifting too far into the physics of brake function, and wandering away from a discussion on the act of reducing the ground speed of an aircraft from landing speed to taxying speed. Think about how you drive your car. Say you were driving along at the speed limit of 80 kph. That's close to the landing speed of a recreational aeroplane. Being an attentive driver, you see that a couple of hundred metres ahead, the traffic lights have changed to amber. Do you stomp on your brake pedal then and there? Nope. You take your foot off the GO pedal and let the rolling and air resistance start to slow your vehicle. As you approach the traffic lights, which are now showing red , you use your experience and decided to lightly press on the brake pedal to get a better rate of slowing. You monitor the effect of that application so that by the time your vehicle is about 30 metres from the traffic lights its speed is down to about 20 kph and so rolling and resistance forces can deal with slowing the vehicle to walking pace. Then you clean up the stopping process by a little more brake pressure application. At no time did you stomp on the brake pedal and cause the brake system to stop the rotation of the wheels completely so that they skid over the road surface. Now, what's the difference between the braking process you have been doing since you were a pimply-faced teenager and the one you employ now as a responsible PIC? In going to Tundra tyres, I would look at the possibility of the tyres interfering with stall characteristics, because they may increase drag, which may affect pitch behaviour. There could be prop-strike problems if the sidewalls flexed too much on touching down. That flexing could also allow the sidewalls to contact surrounding assemblies, damaging the tyre, and even the assembly.

Questions! Questions! Questions! The more I delve into planning this thing, the more questions pop up. This one is about the timing of aeroplane dispatch at the start of the event. Here is my idea of the distribution of areas of activity on the aerodrome: I'm expecting that in April, we will be using runway 04. What I was planning was that competitors would gather in the marshalling area according to a pre-determined departure order. The first off would taxi down to the 04 Run-up bay. As soon as they entered the bay and began their run up, the Marshall would release No 2 to begin taxying towards the run-up bay while No 1 did the run-up. By the time No 2 reached the run-up bay, No 1 would be lined up on 04 for dispatch. No 2 enters the bay and No 3 is released. The Marshalls at each end of the taxiway would communicate by flag. No need for communication by radio with competitors. From the marshalling area to the run-up bay is 800 metres. At a walking speed of 5 mph (130 metres/minute) that distance would be covered in 6 minutes. The question is: What is the average time for to complete run-up checks?

YAF = Young Aggressive Female The type of female who drives like a maniac and then abuses you, calling you a male chauvinist pig.

I lived on a street with a school zone. Didn't go out much. Hell hath no fury like a YAF driving in a school zone.

There appears to be several car engines available that have been set up for operation in aircraft. OEM spare parts for them are available from the car people. How does that work under the Regs?

I feel sorry for the poor drivers of those juggernauts who have to get them through tight roundabouts while dealing with the impatient "me first" motorists.

Has your enquiry been answered? That's important. If it has, then we can go waffling off on this side track without upsetting you.

Not having done any tests myself, but referring to some published figures, the Coefficient of Friction of steel on steel ranges from 0.5 to 0.8. The CofF between wood and metal was given as 0.2 to 0.6. Basically that says that there is likely to be more sliding of steel on wood that simply steel on steel. Just to clear things up, the Coefficient of Friction is the ratio of the downward force generated by an object due to the acceleration due to gravity and the force required to move that object in a direction other than down. Initially when you start to move one object over the surface of the other the microscopic lumps and bumps on both surfaces interlock, making it necessary to use more force to move the object you want to move. That friction is called static friction, and is the highest value you will get in your test results. Once the object you want to move gets going, the force required to keep it going is less. That's kinetic friction (kinetic = moving). I'll use this graph simply to illustrate the shape you get if you graph the instantaneous CofF over time. Only look at the red and black lines and think of the label on the bottom being Time. Initially the CofF is high (static friction), then it decreases. In the example of the steel, once the steel gets moving it's easier to move it. Remember pushing a car? Similar thing.

I read it s putting on Tundra tyres.

Thanks for that comment. I will have to take that into consideration when organising departures. I won't be doing all the planning myself. I'll have CFI's to give input, and people who have competed in similar events to give me a debrief. Don't forget I've just started this planning process so I don't have all the answered. Heck! I don't think I know all the problems. Here's one to mull over: The event is open to persons with a current permission to fly from a licensing authority . CASA says 15 years old to fly solo on a student licence and 16 for what I'll call a go anywhere pilot's licence. CASA does not specify an age for a commercial licence. It is usual for race rules to require that an entrant who is under 18 years of age to provide written permission from a parent or guardian to participate in the event. Should the rules exclude a 17 years 6 months old licensed pilot without the permission to participate? The kid can legally drive to the airport without permission. I'm the one who is making the rules for the event. The reason I ask is that I want to invite the Scouts Aviation Activities to participate. There could be other Young People too who are not in that mob.

Well, that's got me gob-smacked. I don't even know how to reply.

BUT: After correct torqueing, may be necessary to turn the nut again up to 30 degrees (in either direction) to locate the hole. With six notches spaced at 60-degree intervals, the castellated nut can only be locked where a notch corresponds to the hole. As fine-tuning the torque is not possible, castellated nuts are better suited to low-torque applications. Is it usual to have a specified torque value for bolting a prop to a hub?

We might know nuthin', but Pprune fellas know f all.

Well, what do you call it when you are flying along, fat; dumb, and happy and your aircraft suddenly drops 50 ft then jumps back to where it started? Or same fat; dumb, and happiness and your aircraft suddenly lifts or drops? When everyone gets the gist of what is being discussed, can't we use layman's terms for the sake of brevity? Or do we have to go through the minutiae of the endochronic properties of resublimated Thiotimoline ?

I missed that source of vibration. I was thinking of the propeller producing Lift longitudinally. All other things being equal, the amount of Lift is dependent on air density. What happens when a plane flies through an "air pocket"? Air density decreases; Lift decreases and the plane moves away from its steady state path. Then it flies out of the "air pocket", air becomes denser and Lift increases. Apply that thought to the propeller at the same time. It seems logical that going through the changes in air density would result in changes in the Lift (i.e. Thrust) forces it creates. Surely that must induce fore and aft vibration that expresses itself at the Boss/hub interface as rubbing. And rubbing induces heat.

Support from CASA ??? You velly funny man. CASA say this https://www.casa.gov.au/sites/default/files/2022-06/interim-air-display-administration-procedures-manual.pdf. It's got more hoops than an ante bellum Southern ballroom.

Isaiah 55:8-9

Not relevant to what I was saying. I was replying to a comment about castellated nuts being retained by cotter pins, but that the cotter pins only stop a loose nut falling off. By the time the cotter pin has saves the nut, the clamping function of the nut/bolt combination has gone with the wind. I was suggesting that if one was to use bolts with drilled heads and shank holes as well as nuts with corner drilled jam nuts, then safety wired the heads of the bolts and the nuts at the other side you would be doubly secure, hence "belt and braces"

Like I said. This would be a fun event to have, until the bloody ambulance chasers got wind of it. You should see the hoops I have to jump through simply to submit an application to CASA to organise the event. I'm sorry to say it, but I've got a few years of life to enjoy and I don't think dealing with vast tomes of rules, regulations and what-ifs? is going to add to that enjoyment. Maybe the best thing to do is say, "here's my phone number. If you want to stop for break at my local aerodrome, give me a call and I'll arrange ground transport"

That's about it. Aircraft owners will have to insure their property against causing injury through its operation, and the organisers will have to insure against the usual trips and falls. Do the ladies of the CWA insure against their cakes causing toe-and-mane poisoning? The whole idea might go to pot if CASA says, "No". I contacted them this morning and they said to send what information I have and they will see if the event can go ahead. Can you all please give a donation of Luck, 'cause I reckon I'll need lots to get past CASA? They even want to charge a fee for assessing the application!

Stands to reason. The bolts are pulling the prop boss and hub together by creating forces acting in a longitudinal direction. At the same time there is that transverse force created by the rotation of the propellers matter. Over the length of time that the engine is running, per flight, minor variations in the speed of rotation can cause microscopic amounts of movement between the propeller boss and the hub. That little bit of "rubbing" creates the heat that facthunter has mentioned.

No argument there. But it's good on internet forums to go wandering down the "Why is it so?" path. If BrenDan is doing work on his own aircraft, then wouldn't it be nice for him to have some background understanding of the hardware available to do the job it is doing?

In order to cut out any need for en-route refuelling, I've redesigned the route, and calculated some indicative times for point-to-point flights. Now it is down to about 2 hours' flight time and about 140 NM. Now the route really does get you Winging down the Castlereagh. Hopefully I can arrange a supply of Mogas at Tooraweenah. It starts at Tooraweenah and goes in a clockwise direction. That will bring aircraft back to Tooraweenah so they overfly and descend to join on the crosswind leg. I think that would be safer than the earlier route which had the potential for straight-in approaches. Indicative Times Route 2.docx

That is quite correct. If you want to go the "belts and braces" approach, why not use an ANH7-xx with one NAS509-8 nut with AN970-8 washers, then safety wire the heads and nuts?