TBM930, Garmin 3000:
When flying many 100’s of miles from where you receive an ATC call, is the barometric pressure being given by ATC for the area I’m currently flying or is it where the ATC is located?
When flying direct-to and then choosing approach, is it necessary to choose arrival as well? I find arrival and approach seem to set up the same course in the Garmin 3000.
Moved to #self-service:atc-traffic-navaids
the pressure is given to where you are flying ( local ) , the moment ATC hands you over to an approach/ tower frequency the local pressure is given to you.
Thank you for that info.
Another question; when ATC gives instructions to climb or descend, what is the rate of decent, how many feet per minute are we supposed to go?
Also when given approach instructions to land, what speed am I supposed to go…I quite often find planes pass/overfly me. I’m flying the TBM930, how far from landing am I supposed to be going my landing speed? I think I may be going too slow too far from landing.
The descent should be at about a 3 degree angle, which is roughly your ground speed in knots multiplied by 5. So at 200 kts, your descent will be 1,000 ft/min. Your landing speed is going to depend on what aircraft you’re flying, but you’ll want to start slowing down when you first begin your descent and be at landing speed well before you reach the runway.
That’s great info for fast calculation to get 3 degree angle of descent…thanks!..does this still apply if ATC tells me to climb during flight?
Flying the TBM930 I usually like to have gear down, flaps down at FAF…so up till that point I think I need to fly faster so I’m not run over.
For climbing, just find the optimal rate based on the performance specs of the aircraft. Basically whatever angle maintains a good steady speed. For the TBM 930 that should be around 2000 fpm. Landing speed for the 930 is between 75 and 85 knots, and you’ll want to be slowing to that during your base turn. Don’t worry about other aircraft going faster or slower. A Cessna 152 will be coming in at around 65, while a CJ4 will be closer to 100.
So applying the formula gsx5=the desired descent rate in fpm to attain a 3 degree glide slope?
That’s not an exact formula. It’s just an easy rule of thumb. Also, ATC instructions use 3 degrees because it’s considered a good descent angle for most aircraft. If you want to calculate the perfect descent angle for the situation, just divide the number of flight levels by the distance. For example, let’s say you’re flying at 25,000 feet and want to descend to 5,000 feet within 75 miles. Every 100 feet equals one flight level, so you want to lose 200 FLs to get to 5,000 feet. 200 divided by 75 = 2.666…
Thanks for that…but I’ll stay with the dumb down formula.
In my original post I asked When flying direct-to and then choosing approach, is it necessary to choose arrival as well? I find arrival and approach seem to set up the same course in the Garmin 3000. Would you have any experience with this scenario?
I haven’t played with the 3000 much in the sim, so I’m not sure how accurate it is in setting a course. In real life, the arrival route (STAR) is meant to guide traffic in the region toward the airport. That region could be 100 miles or more. Once you get within 10 or 20 miles of the airport, the approach (ILS or RNAV) will guide you to the runway. You choose an arrival based on which direction you’re coming from. The approach is based on the current weather and which runways are in use.
Many airports do not have arrival procedures butmost have approach procedures. You do not have to load an arrival procedure if you don’t want to.
To sum it up. Arrival (STAR) is a planned procedure to get you from the direction you are coming from to to position where you can start the approach procedure. It is used at busy airports to get all the arriving ducks (A/C) int a row to start the approach.
The approach is where the A/C start their coordinated approach to the runway.
STARS also take into account terrain restrictions soa safe arrival profile is flown.
As for speeds etc. all said above are valid. As a rule of thumb, at the FAF or 1000 ft AGL you should be setup on speed with the A/C in the landing configuration. Its called a stable approach in aviation terms.
Hope this helps
Kev M
Great info from both of you…makes a lot of sense the way you’ve put it…many thanks again!
Just a note, I assume if using the arrival as well as approach then you would have to know your approach first to co-ordinate…correct?
Thats the way to do it. ATC nominates the runway in use & quite often the approach in use espacially if weather is not good or for traffic sequencing. Depending which direction you are coming from, you select the arrival that gets you to the start of the approach. At times ATC will nominate an arrival, taking into account the direction that you are coming from.
Kev M
Yeah, you need to make sure they have a common fix or waypoint. In other words that the end of the arrival connects to the start point on the approach (called an initial approach fix, labeled IAF on approach charts).
Thanks for that info!