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Maarten
16th May 2002, 07:12
Can anyone help me with the following: in the AIC for the Aerofair it is mentioned that a temporay VFR hold may be required between Willingdale airfield and the Doddinghurst mast.

Never having been asked to fly a VFR holding pattern, could somebody enlighten me if how this is flown, clockwise/anti-clockwise?
Thanks.

Maarten

QNH 1013
16th May 2002, 07:36
A standard hold is right-hand and at the speeds and heights we fly is defined as having a one-minute outbound leg from abeam the holding facility before commencing the inbound turn (in still air.) The inbound track is also specified.
The holding facility can be an NDB, a VOR, or a defined DME distance on a particular radial from a VOR, or the intersection of two defined VOR radials. Presumably it can also be a VRP if flying in VMC?
If a hold is left-hand, it will always be stated clearly that it is a left-hand hold; otherwise there would be chaos.

englishal
16th May 2002, 08:56
One minute Inbound leg.....;) Adjust the outbound leg to obtain one minute inbound...

Cheers
EA

Maarten
16th May 2002, 09:31
Thanks for the advice.

Maarten

QNH 1013
16th May 2002, 09:53
I forgot to add that all the turns in a holding pattern are flown at rate 1 (which is 3 degrees per second), so each 180 degree turn should take 1 minute. This gives a total delay of four minutes per hold. (Simple case).
I wouldn't be surprised to find that whole books have been written about the hold.

skyraider
16th May 2002, 13:59
QNH... I think I understand your explanation, which is a good thing, but the only question I have is when to fly over the holding point.

Do you enter the holding pattern by flying overhead the holding point on the outbound leg or do you go overhead at the end of the inbound leg....:confused:

edited: you're post said join abeam the holding point so I assume this means that the inbound leg is flown along the track specified to overfly the holding point before a rate 1 turn right for the next outbound leg. If this is correct my question now becomes...

Do you have to position to join at the beginning of the outbound leg irrespective of where you are coming from or can you join on the inbound depending on your track in relation to the published holding track

cheers
Sky

QNH 1013
16th May 2002, 14:45
Sorry if I've confused you. I've not seen the AIC you refer to but I assume that for the purposes of this AIC that you will already be flying the same track as the inbound track of the hold. You therefore start the hold as you pass over the holding point and begin an immediate rate one turn to the right. The 'RT call is ENTERING THE HOLD.
If you were coming from the opposite direction the RT call as you passed over the holding point would be JOINING THE HOLD. You would then have to fly a reversal to get you back to the holding point in the right direction. This would be either a parallel join or a teardrop join. I doubt if this will be the case with the AIC you have seen.
The hold starts when you cross the holding point and begin the rate one turn to the right. However the timing starts from wings level abeam the holding point on the outbound leg, You have to do the timing and timing correction on the outbound leg because:
1. The ICAO proceedures are defined this way.
2. You can't directly adjust the timing on the inbound leg. As soon as you reach the holding point you have to start the outbound turn.

If someone can copy the relevent bit of the AIC here I'll try and talk you through it.

slim_slag
16th May 2002, 16:56
Ah, the IFR Warriors are out in force today :D :D :D

Why not just pick a point on the ground and fly round it. It's VFR, what do you need to look at these nasty instruments for? You might get totally confused and hurt somebody ;)

Maarten
16th May 2002, 18:17
The relevant section of the AIC is copied below:

"Should circumstances dictate, pilots may wish to establish a right-hand VFR hold between 1,500 ft QNH to 2,000 ft QNH holding East of a line drawn between Willingale (active) airfield and the Doddinghurst mast in the vicinity of Ongar town. This hold is approximately 5 nms to the East of North Weald. Pilots must maintain a good look-out while operating in this temporary VFR hold"

I think slim_slag may be right the two turning point are in a north-south direction, to the east of North Weald. There is not a clear cut inbound and outbound direction.

Maarten

slim_slag
16th May 2002, 18:37
The AIC defines a general area defined by visual ground references, where it is suggested you might light to fly around between two altitudes.

I hate to be cynical, but if I was heading that way I would totally avoid that 'VFR holding area'. All these guys flying around doing their rate one procedure turns, looking at their watches, calculating wind speed and direction so they get their inbound leg close to a minute, making sure they call out on the radio where and where they are with respect to some VOR radial intersection they have just invented, but nobody else knows where the hell it is.

I thought I understood all this stuff but my head is now spinning:D :D

Stay well away from there! Some idiot with his head in the cockpit might bump into you.

I wonder what was it like to live back in the days when you didn't need electricity to make a plane fly.

:D :D :D :D

Missed This!!!!

If a hold is left-hand, it will always be stated clearly that it is a left-hand hold; otherwise there would be chaos.

IFR talk here boys and girls!

Planes will be assigned holding altitudes which ensure vertical separation, so even if one plane incorrectly holds in the opposite direction to the others there will not be 'chaos' in the hold. IN fact if you were in IMC you wouldn't even know somebody else was playing the fool.

As was correctly pointed out, you (generally) fly a hold so your inbound leg time is the same for all aircraft, and as aircraft fly at different speeds and never get it quite right, two planes flying a hold at the same altitude would eventually collide even if they were both flying left hand turns.

The 'direction' of a hold is specified to ensure the plane remains within protected airspace. Using a simplistic example, if the hold is 'left hand', and you fly it left hand, you will not hit anything on the ground. If you fly it 'right hand', this guarantee does not apply.

Clear as mud???

QNH 1013
16th May 2002, 18:41
(Consults Map). Well the inbound track looks like 005 degrees to me, but I am concerned that the holding point is not defined because this produces conflicts between a/c turning outbound and aircraft turning inbound if the all hold at different points. A road crosses the track about mid-way which would do, but you can't be sure everyone is holding on the same feature.

In these circumstances I'm inclined to agree with slim_slag. I don't think I would want to be holding on the defined line if there was a delay affecting many aircraft.

Anyway, hope all the above has helped.

QNH