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Separation?


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I just want to run this past a few of you, for comment and hopefully nice ones to improve my skills.

 

Yesterday, I was commencing takeoff roll on Runway 36 at Shepp, when I heard a twin from a nearby flight school announce his inbound at five miles to the east. As is my habit, I gave a Rolling runway 36 call to give him a heads up, because I knew we would be in the vicinity of each other fairly soon.

 

My takeoff was normal, and in accordance with my intruction, flaps up at 200AGL, then as I was preparing to switch off the fuel pump at 500AGL I looked to my right, and at about 45 degrees high, about 300ft above me was the incoming twin.

 

I could not see the cabin windows but I had a good look at the oil stains under the cowlings as he went overhead.

 

I was to have turned crosswind at that time, but considering the view of the stained aluminium, I decided to abort and continue with the runway heading to 3Nm north of the strip, and I made a left turn to Undera - with a departure call, I might add.

 

What I want to know was did I stuff up?

 

Did I cause the breakdown in separation?

 

Ben

 

 

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Let's see - YSHT - elevation 374ft. So circuit height for our type of aircraft (Jabiru's Tecnams etc) is 1400ft. :thumb_up:

 

The twin should be in the next level at 1900ft for the circuit. By your estimation (500 AGL + 300ft) he/she was at 1200ft altitude. :yuk:

 

You were very lucky Ben - How could it be your fault? Incoming aircraft should arrive at correct height for their performance. I would have thougt a 10 mile inbound call would have been the go for a twin. i_dunno

 

Did you get a chance to talk to the School who owned the aircraft? 088_censored.gif.2b71e8da9d295ba8f94b998d0f2420b4.gif

 

I always look at overflying too close to the end of a runway as asking for trouble (a 100hp Rotax in a RAA craft with one person on board and a stiff headwind can make the aeroplane climb like a homesick angel) (and still be over the runway at circuit height) - I also like to fly over perpendicular to the active/main runway.

 

regards

 

 

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Guest pelorus32

G'day Ben,

 

interesting.

 

So let's look at this.

 

  1. Circuit height is 1000' AGL except if he was classed as a "high speed" when it is 1500' AGL;
     
     
  2. You were at 500' AGL
     
     
  3. You reported him at 300' above you or 800' AGL
     
     
  4. If he was coming from the east then he was coming from the dead side and should have made a joining crosswind call as he came over - at circuit height. My view is he didn't have to cross overhead higher;
     
     
  5. Let's assume that he was making a 1000'AGL circuit;
     

 

There are lots of ways this could have happened. Probably the simplest explanation is that he was on crosswind and he was north of midfield. You may have been in error in estimating his height - let's say by 100 feet (that's him at 900'). Let's also say that he was in error by being 100' low. There you have it.

 

He should have made a joining call (P224 VFG). But it appears he didn't.

 

So, you're alive, a miss is as good as a mile and I hope you aren't sweating too much.:big_grin:

 

Is it an incident though and does it need reporting? Probably not, but I'd be interested in others' views.

 

Regards

 

Mike

 

 

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Ben, did you do a radio check?...If your radio wasn't transmitting then he may not have know you were there...Not that that would have been a sufficient excuse to overfly that location at that altitude..

 

I can't see any mistakes made by you mate...Those fast moving twins can be a bugga in the cct..hehe

 

 

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another thing ben, you say this guy called while you were rolling and he was at 5 miles, then when u reached 500 feet he was on you.. not sure what aircraft you fly but at an average of 500 ft /min climb we could expect that you were no longer then 1 minute total time from rolling to reaching 500ft, so he got 5 miles in 1 minute.. That puts his speed at 300 miles per hour..

 

So either he's in a rocket ship, or he missjudged his distance (grosely) from the airfield..

 

So what facts do we have....

 

1. He hasn't called joining crosswind..

 

2.He's 200 feet below cct height and in the vacinity of the crosswind - initial leg junction,

 

3. He's probably missqouted his distance from the strip by more the 200 %.

 

sure it wasn't a rex plane??006_laugh.gif.0f7b82c13a0ec29502c5fb56c616f069.gif006_laugh.gif.d4257c62d3c07cda468378b239946970.gif114_ban_me_please.gif.0d7635a5d304fa7bdaef6367a02d1a75.gif

 

sorry..couldn't help myself..

 

so i'd say he's guilty of poor, innacurate flying and poor use of the radio.. Something that you'd expect from say an early student..so perhaps it was a student on an early nav or something..

 

I probably would have done 1 thing differently, instead of continuing to climb out straight ahead, i would have turned crosswind and kept that dude eyeballed..I get the hebbie jeebies with my back turned to fast moving acft..just a thought

 

cheers

 

 

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Thats why we have see and avoid!

 

You saw and you avoided!

 

I had two a/c pass under me yesterday 500' in it. Another reason to fly the levels. But geeez they appear out of nowhere pretty damned quick!

 

J

 

 

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It only takes 1-2mb, (30-60ft), difference in settings of either aircraft to close the 'gap' just a little more. This especially if the inbound aircraft is using area QNH and locals are using airfield height settings.

 

I'm finding that it's important to be closer to the midfield, (rather than the threshold),when joining overhead in the midfield-crosswind join. This usually ensures even the RV's can't reach your altitude as you cross the active runway.

 

Low wing twins don't have particularly good visibility in the 10-7 and 2-5 fields of the clock either

 

cheers,

 

 

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Well said Poteroo, and when you joing mid cross or downwind at 45 degrees you are merging with any potential traffic and at a slower closing rate than with a decent over the threshold.

 

Also them quick climbers like Savannah's Tecnams etc find it harder to get ya!

 

J:wave:

 

 

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