Question on steep descents into airspace

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Casimir
Posts: 26
Joined: Sat May 19, 2018 9:14 pm
Location: KOLV

Question on steep descents into airspace

Post by Casimir »

I just completed the CAT 7, and my flight through it made me consider other pilots methods and opinions on descending into an airport from an altitude that's fairly high when only a short distance from it.

I was cleared through Ontario class C, flying at 4500. It was pretty busy, so I waited for the hand off to El Monte tower. Since I'd been given permission to cross the class C at 4500, I was hesitant to descend until I was given the frequency change. It was given after I'd flown to within just a couple miles of the class D of KEMT, so I quickly began to descend and contacted El Monte tower, which granted me permission to land runway 19. However, I was still really high, 4200 feet, so I had to drop some flap and slip the plane to keep my speed down while descending rapidly. Doing so was certainly unconventional and probably not what one would / should normally do under such circumstances.

So my question is what should I have done instead? Should I have continued a standard rate descent (800 feet or so - Cessna 172) and requested flying the pattern? Should I have elongated the base leg a bit more? Should I have made a request to SOCAL Approach to descend after I'd cleared the class C? Situations like this are things I'm not that informed on and am curious how others deal with it, or what real world situations like this would require.
Cessna N5351E (A2A C172 / REP XPlane 11 C172)
Piper N5351A (Carenado Seneca V)
Keith Smith
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Re: Question on steep descents into airspace

Post by Keith Smith »

It's 11nm from the edge of the Class C to EMT. That was plenty of room to descend.
I was hesitant to descend until I was given the frequency change.
It's really important to understand that ATC is not providing any separation between you and anyone else when you're in Class E airspace. Therefore, you shouldn't have any qualms at all about starting your descent. If the radio is busy, then start your descent and advise ATC when it's less busy. You absolutely should not hold off on a VFR descent in Class E airspace because of a congested radio.

The permission to transition the Class C at 4500ft doesn't have any bearing once you leave the Class C.

All that said, if you end up high in the pattern, you shouldn't commit any unnatural acts to come down in a hurry. Simply alter your pattern entry to lengthen the flight path. You can request an overhead crossing and make a downwind entry on the other side of the field, or request a 270 on the base to rejoin the final, or request a 360, etc. What you should not do is point the nose down at the airport, drop the flaps, close your eyes and hope for better days ahead :)
Casimir
Posts: 26
Joined: Sat May 19, 2018 9:14 pm
Location: KOLV

Re: Question on steep descents into airspace

Post by Casimir »

Keith Smith wrote:It's 11nm from the edge of the Class C to EMT. That was plenty of room to descend.
I completely agree - with that much room there shouldn't be an issue. However, I didn't start my descent until I'd reached the outer edge of the class D of El Monte... which only gave me 4 miles to the airport. More below.
Keith Smith wrote:It's really important to understand that ATC is not providing any separation between you and anyone else when you're in Class E airspace. Therefore, you shouldn't have any qualms at all about starting your descent. [...] The permission to transition the Class C at 4500ft doesn't have any bearing once you leave the Class C.
Okay, thank you for that information - I had a more constricted interpretation of ATC clearance, which is why I mentioned the hesitation to begin my descent until after I'd been either cleared to do so by ATC or given the hand off to El Monte tower. Some of the VFR based ATC instructions and how they apply I'm still learning; most of my background there comes from flying a lot of IFR flights where there's a lot less room to maneuver (excuse the pun).
Keith Smith wrote:You can request an overhead crossing and make a downwind entry on the other side of the field, or request a 270 on the base to rejoin the final, or request a 360, etc.
I'll certainly do that if I find myself in a similar situation in the future. It really wasn't my intention to turn my 172 into a diving fighter plane for a few thousand feet... I was just worried that by missing the runway I'd create worse problems for myself. Ironically, the opposite is the case... but sometimes you aren't thinking that way when confronted with it in the sim and have to make a quick decision as the distance is winding down. Just another situation that can be chalked up to a learning situation - due to my ignorance on that aspect of ATC clearance I ended up not being able to follow my pre-planned descent goal; always be thinking of a backup plan.

Thanks a lot for the info Keith!
Cessna N5351E (A2A C172 / REP XPlane 11 C172)
Piper N5351A (Carenado Seneca V)
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