CASE III Marshal stack shenanigans

I have been working on my CASE III skills lately (Hornet). Catching either of those 4 cables after the entire procedure, is one of the most rewarding feelings I ever had in DCS (especially in VR). Catching the 3rd wire being probably the most rewarding experience :P

There's definitely room to improve my Marshal stack --> landing config procedure though.

I was wondering, is there a trick to getting the 2min left hand turns right? For instance, I'd say at 250kts, a certain bank angle should always result in the same turn time (with minor variations due to wind speed maybe). Or am I missing something?

Also, how strict is this Marshal stack procedure irl?

I mean, is the pilot allowed to make a shorter/faster turn in order to achieve the correct commence push time? I can imagine the correct push time being far more important than the "2min turn - 1min leg" rule.

As G B wrote sometimes back: anything is allowed for you to do that makes you commencing at push time. You don't need to make 2 min turns with accuracy to a second. For instance I always make 30° degrees turn and watch the clock, how much does it to take a 180° or 360° first. Before starting the next turn at holding DME, I look at the clock for the time to go, and deduct the time of two 180° which gives you the time you have for the two straight legs. So start the "last" racetrack, fly a 180° turn, fly downwind as calculated for the straight leg, or rather a bit shorter to correct for ship travel, and then turn back another 180° and watch the DME counting down to your distance of commencing, and follow the clock. Then you can play a little with the speed to commence on time.

What Razor said.

What I think really changed things for me was holding at 300kt GS (another GB hint). So that's my single greatest recommendation. At 300kts GS, you'll always be covering 5 nm in a minute, no matter the wind. This precludes the use of ATC during your holdings, since you have to constantly account for wind speed/direction.

What I've been doing as of late is flying 4 min circles 5 nm (or 1 min) behind assigned marshall fix. That way I have a 1 min buffer to compensate deviations in my holding pattern and arrive at the fix on time. Finally, to fly a 4 min circle use the ADI to help you fly a half standard rate turn: in other words you'll cover 45 degrees every minute.

PS: oh, and draw everything out in a piece of paper. That way you know where your're supposed to be at every minute before your push time and adjust accordingly.

Exactly as Razor said. Don’t think of the “2 minute turn - 1 minute leg” as a rule. It’s just “gouge” one can use to create a plan for how you are going to make your push time.

As for timing your turns, one way to do it is to reference your standby attitude indicator (immediately below the right DDI). You’ll notice at the very bottom of the gauge (below the slip ball indication) is a white needle with three white reference marks.

The white needle will be aligned with the center reference mark when you are not turning. As you turn, the white needle will deflect left or right depending on your direction of turn. Assuming a left turn in the marshall stack: A one needle-width deflection (needle halfway in between the center and the left reference mark) represents a 90 degree per minute rate of turn. A two needle width deflection (white needle lined up with the left reference mark) represents a 180 degree per minute rate of turn.

So, if you want to complete a turn at one end of your holding pattern (180 degrees) in 2 minutes, you’d adjust your AoB to keep that needle displaced halfway between the center and left reference marks.

Once you get established and stable with the correct turn needle displacement then can see what angle of bank that results in for your given airspeed and rely more on the hud.

That’s probably the hard way, lol. I’m sure GB or any DCS hornet pilot who has played around more in the stack than I have to this point can likely just spout off a good AoB that gets you in the ballpark at 250 knots. Still, not a bad idea to know how to reference/utilize the turn needle as that will work for any airspeed you happen to be holding at.

Exactly as Razor said. Don’t think of the “2 minute turn - 1 minute leg” as a rule. It’s just “gouge” one can use to create a plan for how you are going to make your push time.

 

As for timing your turns, one way to do it is to reference your standby attitude indicator (immediately below the right DDI). You’ll notice at the very bottom of the gauge (below the slip ball indication) is a white needle with three white reference marks.

 

The white needle will be aligned with the center reference mark when you are not turning. As you turn, the white needle will deflect left or right depending on your direction of turn. Assuming a left turn in the marshall stack: A one needle-width deflection (needle halfway in between the center and the left reference mark) represents a 90 degree per minute rate of turn. A two needle width deflection (white needle lined up with the left reference mark) represents a 180 degree per minute rate of turn.

 

So, if you want to complete a turn at one end of your holding pattern (180 degrees) in 2 minutes, you’d adjust your AoB to keep that needle displaced halfway between the center and left reference marks.

 

Once you get established and stable with the correct turn needle displacement then can see what angle of bank that results in for your given airspeed and rely more on the hud.

 

That’s probably the hard way, lol. I’m sure GB or any DCS hornet pilot who has played around more in the stack than I have to this point can likely just spout off a good AoB that gets you in the ballpark at 250 knots. Still, not a bad idea to know how to reference/utilize the turn needle as that will work for any airspeed you happen to be holding at.

Always learning. I'd never looked at the standby and did not know about the needles. I'lltry to fly off of that on my next 4 min circles. Thanks! Also, I think I said 1 min per 45* on my post above when I meant 1 min per 90*

I would add here that, while in the Marshall Stack, the only requirement that absolutely MUST be observed is your altitude assignment. Think of this approach procedure as a way of parking you in a spot where you are safe from mid-air collisions with others waiting to make their approaches. The second most important thing is to be at the approach fix (that Tacan bearing and distance from the boat) on time to "commence" your approach. How you get there is not so important. :thumbup:

From many years as an ATC I always fly IFR turns at rate 1. This is 1min for 180deg or 2 min for 360 deg.

I make my leg lengths standard 1 or 2 min until the final one. (1 min legs give a 4 min hold, 2 min legs give a 6 min hold)

On my last hold. I establish outbound abeam the descent point. (i.e if I turn outbound at the descent point I will be on outbound leg abeam it). I then check the time. Calculate the time left to push time. Subtract 1 min and half it. That gives my leg length. very simple and quick to do.

e.g. push time = 30; rollout at start of outbound leg at time 26:30;

i.e. 3:30 until push

- 1 min for the turn = 2:30

therefore each leg = 1:15

I will commence my inbound turn at time 27:45.

Any wind effects are minor enough to adjusted by throttle on inbound leg.

Thanks guys, a lot of useful information in this thread :thumbup:

ADI has turn rate also; easier to reference than the standby indicator.