ILS RWY 35 @ KAVL
We have 5 depicted fixes to cover. NDB BRA, VOR's SUG and SPA and Intersections FREEZ and TUXDO. We'll try to cover these points quicker but I'll spend some time with FREEZ and some hypotheticals.
We'll start with the VOR's. Neither SUG or SPA are approved approach fixes. The depiction of SPA is there purely to identify the TUXDO intersection. The depcition of SUG is there because radials of off SUG are used to identify TUXDO, the FAF at UMUXE, an additional fix at OBOVE and radial 312 is used during the missed approach as both a radial to track and the radial on which to eventually hold.
Arguably, SUG radial 233 and the localizer could be used to identify BRA if you weren't equipped with ADF but it's not actually depicted as such and the plate does specifically state ADF is required so I'd have to defer to the regulations and when/which substitutions are allowed. We'll cover SUG Radial 233 a bit more momentarily with the FREEZ intersection since the FREEZ is more or less reciprocal (Bearing 055 or radial 235 @ 18.4NM vs radial 233 @ 18.4NM gives a position error of about 0.6NM)
NDB BRA. Like MULEE in the previous approach at KFAR, BRA is both the IAF and IF for this approach. When coming from a direction due West, North or East of BRA, the expectation is that a procedure turn is required to comply with Rule #1 and set yourself up on the Final Approach Course. When approaching BRA from the South, you have rule #2. Positively identifying your location. You'd overfly BRA as the IAF to establish your location, execute the procedure turn and overfly BRA a second time, this time as your IF. Rule #3 would apply if you were above 5,200ft but as the procedure is a hold-in-lieu, ATC probably has already stepped you down to the required altitude.
TUXDO. TUXDO is itself an IAF so when TUXDO is used, BRA is no longer your IAF/IF, it is only the IF so no PT is necessary. No PT is also necessary because TUXDO meets all the requirements you need for Rules 1-3. It's on the final approach course so there is no excessive turn to final approach complying with Rule #1. It and your position can be positively identified by intersecting VOR radials complying with Rule #2 and if you fly to TUXDO via SPA, you have some 33NM to get down to 5,200 ft before BRA, at a nice leisurely descent of 3-ish (3.3) degrees that's enough distance to descend from 16,200 ft to 5,200 ft at 600-700fpm and 120kts and no winds (tailwind will require faster descent/headwind slower).
Last but not least FREEZ. FREEZ is not listed as an IAF/IF. FREEZ depiction on the chart is largely irrelevant to the approach however, it is likely depicted due to the "high terrain" located under FREEZ and because it is a prominent enroute fix on V222 off the SUG VOR. You'll note that the approach plate clears you to 6200 ft between FREEZ and BRA which is interesting since the BRA NDB is almost directly below V222 and V222 has an MEA of 6100ft, the reason for this is probably both due to terrain and for separation with other traffic already in the approach/hold which begins at 5,200.
Let's say there was no other traffic but say terrain in the area requires you to be at 8,000 ft inbound from FREEZ... If you have to get from 8,000ft at FREEZ which is not an IAF or IF and flew the approach "starting" at BRA as the IF make your turn inbound on the approach at 8000 ft, which is 2800 ft high. You'd then have to come down 4,000 by UMUXE which is the final approach fix 4NM away from BRA. If you're going 120kts, that's a descent rate of 2,000 FPM to reach UMUXE at the correct altitude assuming an immediate change from level flight to 2000fpm descent, an immediate change from 2000fpm descent to something more "stable" say 500fpm a the bottom of the descent and with no time to prep the plane for the final approach. That's not only unstable but uncomfortable and unnecessarily stressing on the airframe both in unloading (negative-G initiating the descent) and loading (positive-G slowing the descent) even if the airframe is capable.
Lets say we go with something a little less uncomfortable or maybe we just decide to stick with the 2,000fpm because we haven't actually hit the FAF yet so stable approach criteria doesn't necessarily apply and hey we had an old-school military instructor for our CFII and he taught penetration/slam dunk approaches in addition to dive & drive and constant rate approaches (it's my understanding the military no longer does penetration/slam dunk approaches as a matter of course unless in a war zone where such a procedure may be necessary due to the protected area surrounding the airport, please correct me if I'm wrong).
OK so we get to the FAF and now we're still a bit high on the approach say 4,500 ft and lets say fast we picked up 30kts in that rapid descent, we probably picked up more but 30kts fast is still enough for this hypothetical/demonstration. We're inside the final approach fix where stable approach criteria does apply but we decide to continue anyway. Our descent rate is still somewhere in the neighborhood of 1000fpm as we have just over a minute at our speed with no wind to get down the necessary 1400ft to 3100ft by OBOVE just 3NM after the FAF.
We manage to pull it off, getting down and getting our descent rate under control but we still haven't prepped the plane for landing and we're still going 150kts or more which is too fast to put the gear and flaps down and it gives us only 1 minute and 15 seconds from the missed approach point at DA minimums which are 750ft below us. We bleed of our airspeed nice and quick without ballooning but now we're high again so we increase our descent rate by finally prepping the plane for landing... Maybe we catch up and are finally setup for landing and on our numbers or maybe we're a still a bit high but we're below the clouds and have the runway insight so we accept the excess altitude as something to manage in the final descent to land past the missed approach point...
Congrats but maybe in all that high workload and rapid fire events you forgot to change your fuel tanks and now you've run out of fuel and have an engine failure on short final or maybe you forgot to put the gear down or maybe you're still much to high to be stable or have a high vertical speed and end up slamming the plane on the ground or still have a high airspeed and land long... That's why stable approach criteria is such an important consideration...
Want to know what would have saved you a whole heck of a lot of work? Execute the procedure turn and get yourself down from the 8,000 ft to the 5,200 feet (or at least something closer to it) authorized before the IF, then execute a nice, comparably leisurely and stable approach to the runway. The average procedure turn adds about 3 minutes to the approach which is a descent rate of 950fpm and that's assuming you execute the procedure turn immediately after crossing the IAF, you have 10 NM which really becomes 20NM (10NM out, 10NM back in) which is enough distance to come down 6,000 ft from 11,200 ft to 5,200 ft at a nice 3-ish degree slope.
