Remind me how to close "The Gate"???

[Keygrip]

Have been reading some of the postings (on various forums [fora? forii?]) about racetrack procedures and holding etc.

Reminded me that in the dim and distant past, I recall an instructor talking about "the gate" in a hold??

What was all that about? Does it still happen? What charitable organisations are around to help you recover after using one?

What was that "gate"? How does it work?

[BEagle]

The only time I've heard anyone talk about 'the gate' was outbound in an NDB hold. But he was one of those irritating people who had devoted hours of time making what is, after all, a fairly basic non-precision procedure into an art form! The sort of person who finds bus-spotting too demanding a pastime!

What's wrong with just hitting the overhead (on a sector 3 or Direct join), turning onto the estimated outbound heading with 3x drift applied, starting the stopwatch at wings level or abeam, and holding heading for the estimated time based on your best guess of groundspeed, I would ask. KISS - it's a non-precision approach!

[Wee Weasley Welshman]

Well its useful to talk of gates with reference to the start of the inbound turn to the beacon.

Assuming at this point that little is known of the actual wind drift conditions it can be useful if Bloggs has an idea whether or not he is tight or wide at the start of the inbound turn. The degrees off the hold axis either side can be considered to form a gate.

I agree too many IR instructors take the black art of the non precision and holding procedure too far in the Nth degree. They may see what they are talking about but Bloggs rarely ever will. Their Art is developed over many hundreds of hours doing the same procedures. Bloggs needs to hang his hat on a concrete structure of repeatable steps to achieve his goal in his limited experience.

WWW

[eyeinthesky]

Oh B***ocks! I had just finished typing a reply to this and my computer locked up, so here goes again. (Maybe it will be more succinct this time!)

The 'Gate' is that point on that beautifully drawn racetrack on the charts when the outbound leg starts to curve round to join the inbound leg. Some people use it to monitor their position at that stage in the hold so that they can have an idea of where they will end up relative to the required inbound track when they have finished the inbound turn.

The way I was taught it (by one of those detailed people you talk of :8 ) was as follows.

For a typical light twin (120kts in the hold) the 'Gate angle' is about 30 degrees off the inbound axis in a normal 4 minute holding pattern.

Consider the following scenario (a pen and paper might help!):

An NDB Holding pattern with an inbound axis of 090M, turning left.

If you were on the perfect racetrack for your hold, the bearing from you to the beacon at the end of the outbound leg (the GATE) would be approx 120M. Therefore, the tail of your ADF needle, after allowance for drift heading, should indicate a QDR (bearing FROM the beacon) of approx 300M. In theory if you start a rate one turn there and maintain it all the way round to your calculated, drift adjusted, inbound heading you will end up on the inbound track.

If in our example at the end of your outbound timing the QDR is 310 degrees, you are wide at the GATE and can expect to have to stop your turn before you reach your inbound heading to intercept the inbound track and then fly your wind corrected heading to maintain it.

If the QDR is 290 then you are inside the holding pattern and can expect to pass through the inbound track before you have completed your turn. You will then have to keep the turn going, reintercept from the non-holding side and then adjust to maintain the track.

The same effect can be had in a VOR Hold by rotating the OBS to 300FROM and the CDI needle will tell you whether the GATE Radial is to the left or right of you (if it is left you are wide and vice versa).

Some people recommend that if, before the end of your outbound timing, you reach the GATE QDR you should turn and fly up that QDR until the completion of outbound timing, This will prevent you being inside the pattern and flying through the inbound axis and having to reintercept from the non-holding side.

The GATE angle will be different for different aircraft speeds. The slower you are the smaller the angle since the radius of turn from outbound to inbound leg is smaller.

Having said all this, I must confess to being more in favour of BEagle's approach than the over-complicated maths approach!
;)

[big pistons forever]

Maybe it is different in Europe but in North America you hardly ever actually fly a hold. In my case I have only flown 3 actual assigned holds ( not counting Shuttle descent non- precision app ) since I got my IFR rating in 1988, and all were to hold on the bearing I was flying to the beacon. The big problem wih a lot of IFR instruction is that instruction time is wasted on IFR trivia like " the gate " instead of teaching pilots what they need to know in order to fly IFR in the real world.

[Chuck Ellsworth]

B.P.F. :

Well stated... :O

Chuck

[I Fly]

It seems I have been using ‘the gate’ for many years without knowing it by this name. But, the angle at the end of the outbound leg does not change with aircraft speed. A faster aircraft flies a larger angle but it also covers a proportionally greater distance on the 1 min outbound leg.

[BEagle]

Big Pistons and Chuck - with you 100% on that!!

I can recall only once having to enter an unexpected hold - inbound to Frankfurt when they changed the runway.

If you're not on the inbound course when you've completed the inbound turn, don't mess about trying to refine things or you're likely to go overhead the beacon on course but way off heading. Just re-home to the facility and re-estimate things next time round the hold!

[GT]

I teach the gate when teaching holds - but with the following proviso to the student.

It's an aid, a means to an end. It's not the be all and end all (the be all and end all being capturing and maintaining the inbound QDM). Use it if you think it helps, don't if you think it doesn't.

Regards, GT.

[eyeinthesky]

Holds are commonplace over here, as we simply don't have the room to stream everyone 500miles out as I understand often happens in US airspace. The holding facilities at BNN/LAM/OCK/BIG for Heathrow for example are rarely empty without someone at the very least doing an orbit for spacing.

It is a good idea to know how to fly one in case you get asked to! It is especially important to be able to work out when to turn in so you don't go out of the protected area and infringe another holding area!

[StrateandLevel]

Closing the gate!

Thats the countryside code: always close the gate to stop the bull shafting the cows in the next field!

[nasib]

"If you're not on the inbound course when you've completed the inbound turn, don't mess about trying to refine things or you're likely to go overhead the beacon on course but way off heading. Just re-home to the facility and re-estimate things next time round the hold!"

Excellent idea. If only someone could convince the CAA that this is acceptable on an IR test!

Nasib

[Keygrip]

Ah, Nasib - you win my prize for being the first one to point out that some people may insist that you can do it - whether you need it or not.

[BEagle]

nasib - sorry, should have made clear that only applies to the sector 3 join. The accuracy of which is at best an inspired guess. But I've seen so many people on IRs in bigger faster things join the beacon, commence the sector 3 join and then mess about trying to sweeten the inbound course 'couching the needle' in an aeroplane with a slow rate of turn. They would intercept the holding course, but go through the beacon overhead still turning and way off heading...... Whereas they should be have been tracking direct to the beacon. Once established in the hold, there should only be a few degrees of correction to be made when inbound to nail the holding course.

[kwaiyai]

Hope you dont mind me changing the thread a bit but would be interested in comments on this. Where I currently am as well as using gate angle during the inbound turn of hold the use of "90" and 45 degree checks are used to check if you are going to roll out on track or not.If you are going to roll out through the inbound QDM the standard proc they seem to use is tighten angle of bank up to 30 degree AOB to hopefully attain the QDM, in a 90 kt Aircraft What do you think?
Thanks in advance.

[pilotbear]

If your instrument flying is absolutley confident and controlled, then tightening the turn maybe an option. I would never personally recommend it because-

1) You may be flying on your own one day in IMC with Icing and turbulence.

2) whilst flying rate one you are in a known controlled situation.

3) notwithstanding the IMC conditions etc. you will be distracted by the attempt to get your inbound QDM and could easily over bank, With no instructor to point out your terminal aerobatics you will spear in (how good is your unusual attitude recovery when you can't sneak a look under the foggles or through the screens?).

If you feel you are going through the QDM continue the rate one turn. Pick a heading to intercept from the other side and stick to it. It will work, it is safer.

Don't forget people who suggest things like steeper turns on instruments generally have more experience than you and can (hopefully) cope with it if it goes wrong.
I wonder how many instructors will tell you to tighten the turn when they can't see out either:ok:

[mad_jock]

I originally got taught the gate method.

But the last IR renewal the examiner showed me a much easier way.

Set the HSI on your inbound track.

Then just keep the ADF needel alligned with the HSI pointer or vice versa. After outbound wind corrected time etc.


Done it in anger a couple of times and it works.

May be someone out there who flys IR more regularly can see any pit falls in this method?

MJ

[kwaiyai]

Hi Pilotbear,
Personally couldnt agree more plus my point is what about rate 1 upto a max of 25 degrees.
Regards :cool:

[pilotbear]

Interesting idea mad jock, however I am always concerned when instrument flying about concentrating on a moving instrument (let alone two) for the reasons above.

Kwaiyai, for a rate one turn to need an angle of bank of 25deg you would be doing a TAS of 180kts (10% of TAS +7kt = bank angle for rate one).

At 120kts 19deg will give rate one if the ball is centred.
Make an early decision as to whether you will fly through your QDM or not then target a heading to correct. Or roll out onto your calculated wind corrected hdg and assess the situation. If you need to correct then pick a hdg, turn smartly onto it and be patient. There is nothing wrong with making large angle intercepts, just don't fly more than rate one in IMC.
Also, concentrate on bank angle, not the turn co-ordinator for your rate one turns:ok:

[mad_jock]

I was concerned as well about concertrating on 2 instruments but it dosn't seem like that if you know what I mean, because you don't have to look at numbers only line the arrows up.


Didn't seem to add anything to the scan .

Just seemed to work. .

Give it a try see what you think.


MJ