rules_of_thumb
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| - | ====== Rules_of_Thumb ====== | + | * |
| - | + | ===== En Route ===== | |
| - | * [[http:// | + | ==== Time ticks ==== |
| - | ======En Route====== | + | Groundspeed divided by 10 gives distance in NM travelled in 6 mins. Use half of this for 3 minute ticks.\\ |
| - | =====Time ticks===== | + | |
| - | Groundspeed divided by 10 gives distance in NM travelled in 6 mins. Use half of this for 3 minute ticks.<br /> | + | |
| e.g. with a groundspeed of 110 kts, the distance flown in 6 minutes will be 11 NM. It will take 3 minutes to fly 5.5 NM. | e.g. with a groundspeed of 110 kts, the distance flown in 6 minutes will be 11 NM. It will take 3 minutes to fly 5.5 NM. | ||
| - | ======Descent====== | + | ===== Descent ===== |
| - | =====Top of Descent calculation===== | + | ==== Top of Descent calculation ==== |
| - | This calculation can be used either to know when to start your descent to an IAF or ATC have given an instruction to cross at or below a certain altitude by a certain point.<br /> | + | * Essentially, |
| - | To find when to start down, multiply | + | < |
| - | To find out how fast to descend, multiply groundspeed by 5.<br /> | + | TOD distance |
| - | Example. We are at 5000 ft and need to be at 2000 ft crossing a VOR. We are doing 100 kts and the DME says we are currently 15 NM from the VOR,<br /> | + | |
| - | 5000 - 2000 = 3 ==> 3 x 3 = 9 NM<br /> | + | ROD = Groundspeed(NM) * 5 |
| - | 100 * 5 = 500 fpm<br /> | + | |
| + | </ | ||
| + | This calculation can be used either to know when to start your descent to an IAF or ATC have given an instruction to cross at or below a certain altitude by a certain point.\\ | ||
| + | To find how far away to start down, find the difference | ||
| + | Example. We are at 5000 ft and need to be at 2000 ft crossing a VOR. We are doing 100 kts and the DME says we are currently 15 NM from the VOR,\\ | ||
| + | 5000 - 2000 = 3 => 3 x 3 = 9 NM\\ | ||
| + | \\ | ||
| + | To find out how fast to descend, multiply groundspeed by 5.\\ | ||
| + | 100 * 5 = 500 fpm\\ | ||
| So 6 miles from now, we need to start descending at 500 fpm to cross the VOR at 2000 ft. | So 6 miles from now, we need to start descending at 500 fpm to cross the VOR at 2000 ft. | ||
| - | ======Approach====== | + | ===== Approach ===== |
| - | =====Glide ratio calculation===== | + | ==== Glide ratio calculation ==== |
| - | Divide groundspeed by vertical speed (in hundreds)<br /> | + | Divide groundspeed by vertical speed (in hundreds)\\ |
| Example: 100 kts and descending at 500 fpm. 100 : 5 or 20 : 1 | Example: 100 kts and descending at 500 fpm. 100 : 5 or 20 : 1 | ||
| - | =====Rate of descent down a 3& | + | ==== Rate of descent down a 3 degree |
| Multiply groundspeed by 5 (or add a zero and half it) to give rate of descent | Multiply groundspeed by 5 (or add a zero and half it) to give rate of descent | ||
| - | =====Height above ground vs distance to runway===== | + | ==== Height above ground vs distance to runway ==== |
| As a glide slope check (or if G/S is not available), multiply nautical miles to go by 300 to give current height above the ground | As a glide slope check (or if G/S is not available), multiply nautical miles to go by 300 to give current height above the ground | ||
| - | ======Cross-wind inbound offset calculation using the clock face method====== | + | ===== Coss-wind inbound offset calculation using the clock face method ===== |
| - | I think this is the easiest method to remember - once you understand how a clockface is involved!<br /> | + | I think this is the easiest method to remember - once you understand how a clockface is involved!\\ |
| - | It can be used for example, en-route for a hold to see how much offset to fly inbound to the beacon. (Outbound is flown 2 to 3 times this value)<br /> | + | It can be used for example, en-route for a hold to see how much offset to fly inbound to the beacon. (Outbound is flown 2 to 3 times this value)\\ |
| - | The key is to see the 4 quarters of the clock face and match the value to the wind.<br /> | + | The key is to see the 4 quarters of the clock face and match the value to the wind.\\ |
| - | So, assuming the wind is going to be coming from anywhere between 0 and 90 degrees off the nose.<br /> | + | So, assuming the wind is going to be coming from anywhere between 0 and 90 degrees off the nose.\\ |
| - | If the wind is 15 degrees off the nose, use 1/4 of the crosswind component. (See the trick? 15 is at the 1/4 past on the clock face!)<br /> | + | If the wind is 15 degrees off the nose, use 1/4 of the crosswind component. (See the trick? 15 is at the 1/4 past on the clock face!)\\ |
| - | If the wind is 30 degrees off the nose, use 1/2 of the crosswind component. (30 is at the 1/2 past on the clock face!)<br /> | + | If the wind is 30 degrees off the nose, use 1/2 of the crosswind component. (30 is at the 1/2 past on the clock face!)\\ |
| - | If the wind is 45 degrees off the nose, use 3/4 of the crosswind component. (45 is at the 3/4 past on the clock face!)<br /> | + | If the wind is 45 degrees off the nose, use 3/4 of the crosswind component. (45 is at the 3/4 past on the clock face!)\\ |
| - | If the wind is 60 degrees or more off the nose, use the full crosswind component.<br /> | + | If the wind is 60 degrees or more off the nose, use the full crosswind component.\\ |
rules_of_thumb.1544130327.txt.gz · Last modified: 2018/12/06 21:05 by 91.177.234.129