Hi Tim, I attempted to complete your 737NG Avanced tutorial but ran into a problem trying to fly the pre-VXV HOLD that your had us program into the FMC. It seemed the 737 could not follow the sharp pattern even with 2-minute legs, and this resulted in the aircraft actually flying a considerable distance away from the planned HOLD pattern. It seems strange that an aircraft would be placed into a HOLD while flying at FL310 @ M0.755. It simply doesn't make sense if the purpose of the HOLD is simply to buy some time. This is an excerpt from an article related to x-minute turns and the required bank angle. Of special interest is the section which states that 2-minute turns are NEVER performed by the 'heavies' at cruise.------------------------------------San Francisco HubProcedures & TechniquesFlying a 2-Minute TurnThe Rate 1 Turn or a 2-Minute Turn, is commonly used procedure. The problem is how to figure the bank angle for the turn as the a/c airspeed will determine the bank angle required.There is an easy formula for determining the required bank angle. It can be figured two ways. The first is to take your current indicated airspeed and divide by ten. Then take 1/2 of your result and add them together to give you the bank angle. For example...Current Airspeed (kias) = 220220 / 10 = 2222 / 2 = 1122 + 11 = 33Bank angle for 2-minute Turn = 33

> Would it have not been wiser to mandate the HOLD at a>much lower altitude and speed?>>Regards>>You're misunderstanding a couple of things:The two minute legs do not imply that the hold takes two minutes. A two minute leg simply means that once the aircraft has rolled out onto a straight leg of the holding pattern, it flies that leg for two minutes before entering the turn to reverse course.So, when flying a hold, when you cross the holding fix, you turn (left or right) at a standard rate or at the max bank angle until you are on the outbound leg. When you roll the wings level, you start timing, and in two minutes you again turn (left or right) at standard rate/max bank and roll back on to the inbound course. You of course alter the outbound leg time and crab angle so that your inbound leg is two minutes long.Your calculations are correct that no airliner at high speeds would try to maintain a three-degrees-per-second standard rate turn in the holds. ATC expects the patterns to get wider as the speed goes up. But that does not affect the leg length in time or miles.ATC will usually adjust the length of the holds to the speed of the aircraft and the expected length of the delay. So if you're going to be held enroute for a while, they'll give you long (30 NM or more) legs. But I've been in a situation where we got a single turn at FL350 because of crossing traffic.There is definitely a problem with the holding pattern depicted on the ND - all that's correct about it is the direction of the turns.I put the hold in the tutorial where it is for a few reasons:I wanted to teach how to define a waypoint by fix/bearing/distance.I wanted to teach how to define a hold.I wanted to put it in an otherwise calm point in the flight - not in the middle of flying the arrival, it would be too much for a novice to keep up.Thanks for your comments and I hope I cleared some things up.

Hi Tim, Thanks for your quick response. Yes I am aware that the leg length is just that, flying the predetermined length of time, hopefully on course, in both directions. As you could see from the article the actual depiction of the HOLD on the ND should have been much, much wider. In fact the aircraft goes so far out of the 'drawn' boundaries that a 2 minute leg might in fact be 5 minutes or more, if ever, because of the difficulty of the 737NG flying the expected pattern at that speed. It takes a long time for the 737 to get back on course. I did alter the time to 4 minute legs and even that was a challenge I will make my next flight have 10 minute legs just so I can get a feel of speed-vs-leg time for a decent visual hold pattern. I am not a pilot but I almost always listen to United Ch-9, ATC, when I fly on commercial airlines and it had occurred to me that I never heard CENTER ATC command a HOLD at cruising altitudes but definitely did hear APPROACH ATC order ones at much lower alttitudes especially in KORD land or KSFO. I had assumed you didn't want to place a HOLD in the STAR because of possible problems new users may be faced with but I just wanted to comment on my opinion of a Hight-Altitude, crusing speed, HOLD. I now understand you considered other factors and that made you decide on the pre-VXV HOLD thus I have no complaint. I also read you on the ND display for a HOLD, especially this one. Again Tim, thanks for your comments.Regards