I want to follow the OOSHN5 arrival route, but i have a few questions about it. How do i know what VS to use in between the WPTS? also what are the numbers under the altitudes with the *?
https://www.ivao.aero/training/documentation/books/SPP_ADC_SID_charts.pdf
Maybe this can help you.
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Or this
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I believe you are to calculate your own VS and just have to meet the crossing restrictions.
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Vertical Speeds are pilots discretion, meaning you can use whatever VS you deem needed to achieve the altitude at the point.
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The OOSHN5 into KBOS is a “continuous descent arrival” meaning you’ll keep on adjusting down to hit at/between targets. A good way to do this is by using In Flight Assistant’s VNAV feature (comes with the GPWS in app purchase-only on iOS as of now iirc) If you can’t use In Flight Assistant to get your speeds and altitudes setup-you can do some simple math if you have a calculator or other device handy. If you’re between 14000/9000 at OOSHN (let’s say 13000’ for the purposes of this) and at 250kt going for 22L (Via GRGIO BRGIT ADDAA LEEZI) and you’ve got 2:30 time to go to GRGIO where you need to be under 9000 you’ll need a VS of -1600 or so to get under 9K at GRGIO. With that in mind, you HAVE to be AT 7000 at BRGIT.
I find that when I need to calculate or input into VNAV-that it’s better to calculate/input the VNAV to the HARD limits-the ones that have two lines above/below them. So say you’re at 13K/250kt at OOSHN-and you’ve got 4:45 time to BRGIT and you need to get down to 7K at BRGIT.
The math on that is 6000/4.75=VS -1263
The IFA VNAV feature is waypoint for waypoint-there’s currently no “look ahead” or profile calculation as it were. If you’ve got two waypoints that are setup close to each other and you put an altitude in-the IFA VNAV will tank you down at -5000 max in an attempt to get there.
The OOSHN is a fairly gentle descent profile save the 4.7 mile run from BRGIT to ADDAA where you’ll slow to 220kt and descend 1000’ in 4.7nm as you’re slowing.
I’ll put a video on this up later on today. I’ve not flown the OOSHN in a while-I mostly use the ROBUC3 and JFUND2 with my VA. Any questions feel free to ask here or in a DM
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