Calm Wind Landings

Some of a pilot’s favorite words are heard on the ATIS:  “Winds, Calm.”  These words set off all sorts of happy bells and hallelujah choruses.  Most pilots spend their lives fighting the winds.  On those rare days when the winds are calm, great happiness ensues.

But, are calm wind landings more complicated then everyone thinks?  Well, they can be if the proper planning doesn’t go into them.

Let’s think about wind.  We have surface wind and we have winds aloft. Sometimes the surface winds are calm.  When this happens, certain airports have preferred calm wind runways which are supposed to be used in these conditions.  Winds aloft are almost never calm.  95% of the time, there is some kind of wind even 100-200 feet above the surface.

Here is the question pilot’s face when coming into an airport with calm winds: which runway do I use?  Do I use the calm wind runway?  Do I use the runway that is easiest to enter the pattern for?  Do I use the one with the shortest taxi?

A lot of technologically advanced aircraft have a wind indicator on the PFD. This tool is often forgotten in calm surface wind conditions.  On the contrary, this is probably the most important tool a pilot can have when figuring out which runway to use when the winds are reported calm.

Here’s why.  That wind indicator is showing the pilot what the winds aloft are. The winds aloft should determine what runway is going to be used.  If the wind indicator is depicting a south wind, then a south runway should be used.  Even if it is a 5 knot wind at pattern altitude, it’ll still be a headwind coming in on final approach.  If the north facing runway is used, that same 5 knot headwind can blow an airplane halfway down the runway before the ground speed drops off enough for it to land.

So, the next time you are coming into an airport and the winds are reported calm, take a look at your wind indicator on your PFD when deciding which runway to use.  It’ll probably save a few go arounds!

Cirrus CAPS pull #55 took place at the beginning of November over Fayatteville, AR.  From initial reports, it appears a clamp broke on the oil cooler, causing a loss of oil pressure.  It does not appear that the engine immediately quit, but an annunciator alerted the pilot that the engine was losing oil pressure.  At this point, it appears the pilot elected to do an emergency descent to an airport below him, but ended up not timing it right, missing the airport and pulling the parachute.

As an experienced Cirrus flight instructor, there appears to be some suspect decision making in handling this operation.  I teach in a Cirrus that if an oil light comes on, given that a pilot has some altitude to work with, it is a better option to physically shut the engine down, leaving control of the situation in the pilot’s hands.  This way, the pilot knows when the engine is stopping and is prepared for it, instead of the engine acting erratically and causing problems on the descent.

After checking the engine gauges and shutting the engine down, a pilot should establish best glide first, not nose down and descend at a high rate trying to make an airport.  Best glide gives the pilot many more options and a lot more altitude to work with, further allowing him/her to plan how to make an airport directly underneath the airplane.

To pontificate, it seems that if the pilot had adjusted the plane to best glide, instead of performing an emergency descent, there is the possibility that Drake Field would have been reachable, the chute would not have been needed, and the driver of the truck would not have had to visit the hospital.  Hindsight is 20-20, but this may be an overall training and decision making issue that may need further emphasis.

The initial NTSB report as well as a link to the CBS story is below.

http://www.cbsnews.com/live/video/pilot-forced-to-deploy-emergency-parachute-in-arkansas/

NTSB Identification: CEN16LA026
14 CFR Part 91: General Aviation
Accident occurred Tuesday, November 03, 2015 in Fayetteville, AR
Aircraft: CIRRUS DESIGN CORP SR22T, registration: N857SW
Injuries: 3 Minor, 1 Uninjured.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.
On November 3, 2015, at 0950 central standard time, a Cirrus SR22T airplane, N857SW, descended under the canopy of the cirrus airframe parachute system (CAPS) and landed on a road in Fayetteville, Arkansas. The pilot, pilot rated passenger and one person on the ground received minor injuries. One passenger in the back right seat was uninjured. The airplane was substantially damaged. The airplane was registered to WG Aviation LLC, Rogers, Arkansas, and operated by a private individual under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident and an instrument flight rules (IFR) flight plan was filed. The flight departed from the Bentonville Municipal Airport (VBT), Bentonville, Arkansas, at 0934 and was en route to the Waco Regional Airport (ACT), Waco, Texas.

According to the pilot, after departure from ACT he leveled off around 10,000 ft mean sea level (MSL) and was in “VFR on top” conditions. The pilot noticed that the crew alerting system (CAS) flashed a yellow caution light for oil pressure; the engine was still producing power. The pilot notified air traffic control (ATC) of the issue and received vectors to the nearest airport, Drake Field Airport (FYV), Fayetteville, Arkansas. The pilot descended and maneuvered toward FYV as the CAS indicated a red warning light for oil pressure, which had dropped below 10 psi. The engine was producing inconsistent power as the airplane descended to 3,300 ft and FYV was still not in sight due to cloud coverage. The pilot was unable to maintain altitude and the airplane’s stall warning horned sounded. The pilot deployed the Cirrus airframe parachute system (CAPS) and descended to the ground. During the landing the airplane collided with a truck and then came to rest on a four lane road.

At 0953, the weather observation at FYV reported wind from 190 at 9 knots, gusting to 17 knots, 10 miles visibility, clear sky, temperature 61° F, dew point 57° F, and altimeter setting 30.11 inches of mercury.

An initial postaccident examination was conducted on November 4, 2015, in Fayetteville. Engine oil was observed on the underside of the fuselage. The oil cooler cross fitting was broken and oil was observed in the engine compartment.

The airplane’s recoverable data module and three data cards were removed and sent to the NTSB Vehicle Recorders Laboratory for download.

The airplane has been retained for further examination.

When I was doing my instrument and multi-engine training, we did a lot of circle to land approaches.  As a student, I could never figure out why these types of approaches would ever be practical when you could an approach straight in to another runway.  But, as a good student, I never asked my instructors the purpose of them, I just did them to the best of my ability.

Now, having been flying in the IFR system for almost a decade, I’m finally beginning to fully understand the practical purpose of a circle to land approach.  I have actually elected to do an approach where I had to circle to land on several occasions in actual IMC conditions.

One important note to remember on circle to land approaches is that the minimum descent altitude (MDA) is always higher than on a straight in approach.  The reason for this is that you are basically joining the pattern for a different runway and you have to be able to visually keep yourself clear of towers and other obstacles.  So, you need a higher visibility and a higher ceiling than if you were just lining up to come straight in.

Here are a couple of practical circumstances where it would make sense to do a circle to land approach.

Airports with only 1 straight in approach

This one is easy.  There are a number of airports scattered around the US that have only 1 straight in instrument approach published for it.  Around my part of Texas, the first one that pops into my mind is the RNAV 31 at T85 in Yoakum, TX.  Most of the year, the prevailing wind is out of the south, so 13 is the favored runway at T85.  During the winter is when most of the IMC weather happens in South Texas, so that is why the approach is for 31.

Of course, especially this year during the summer, there are some IMC days where an approach to T85 would be necessary.  When there is a strong wind out of the south, landing on 31 is impractical, so a pilot would fly the approach to 31, then circle to land on 13.

Approaching from the opposite direction

Take a look at the RNAV 19 at KBMQ, Burnet, TX.  The two initial approach fixes (IAF) are IXANY and JIBAJ.  If a flight is approaching BMQ from the west or north, this is an easy approach to join.  If a flight is coming from Austin (directly the the east and a little south) or San Antonio (almost directly south), it would be a bit of extra flying to get configured properly for the approach.  Especially coming from Austin, because the degree of turn to join at JIBAJ wouldn’t make the approach practical.

Well, how about vectors?  Unfortunately, Houston Center doesn’t have this approach depicted so vectors aren’t a possibility.  Center can give you vectors north to make the angle a little easier to join at JIBAJ, but they can’t vector you onto the approach.

Direct DLORA to join is another option, but again, if you are approaching from the southeast, the angle is wrong.

Insert the RNAV 01 approach with a circle to land.  AMUSE is right on V163, so it’s really easy to join the approach there coming from the south.  Coming from Austin, joining the approach at SUBIE works out great. Fly down to the MDA, join the left downwind for 19, and everyone is happy.

VOR Circle to Land Approaches

Every instrument pilot has had an instructor “force” them to do a VOR A or VOR B approach and no one enjoys them.  I personally think they are good practice.  With the number of RNAV systems and RNAV approaches out there, though, VOR approaches are becoming a bit archaic.

They do have a place in this discussion, though.  A VOR approach is given an A or B designation when the angle of the final approach course is greater than 30 degrees to the runway (VOR A KLZZ), or the final approach course is lined up with the runway, but the MDA is too high to practically descend and land (VOR A KGRK or the VOR/DME C KASE).

So, there are practical uses for a Circle to Land approach.  The next time you do some IMC work with an instructor, ask him/her if you can include one.

The massive storms that rolled through the Austin Bergstrom and San Antonio areas last Friday not only put a dent in the landscape, they put a dent in the skies too.

The Austin Bergstrom (KAUS) control tower suffered significant flood damage Friday.  6 inches of rainfall in an hour caused water to come pouring into the first floor of the tower, flooding the radar room and knocking out the power.  This led to transmission outages for the tower, ground control, clearance delivery and the ATIS.  Similar to the Chicago Center fire last year (though this was a much smaller section of airspace), the area normally controlled by Austin Approach was replaced by a big, gaping radar hole.

By 8:45am on Friday morning, the Austin Bergstrom airport actually closed.  One runway eventually opened back up Friday afternoon, but massive delays and cancellations had already taken place.  All the ILS approaches were down and Houston Center had taken over the airspace normally occupied by Austin Approach control.

A temporary, emergency tower vehicle was brought in by the FAA (it’s essentially an RV with communications and a giant window) by the end of the weekend.  All arrivals and departures were restricted to 17L and 35R.

Due to the radar outage, I heard there was as much as a 4 hour delay even for planes coming into Austin Bergstrom from Dallas, and that was in VMC conditions on Sunday and Monday.  Tuesday and Wednesday brought IMC conditions which only enhanced the delays.

The latest news is that Austin Approach will be opening back up, but in a satellite base in San Antonio.  The Austin controllers will be using the SAT radar room and will be receiving their radar picture via satellite.  The approach frequencies should be up and running today or tomorrow.  The Austin Bergstrom tower is up and running and most of the ILS approaches are operational at this point.

In the meantime, expect delays going in and out of Austin.  If you don’t have to get to AUS, EDC, or GTU, you’re better off delaying a day or two until Austin Approach is back up and running.

Most pilots have seen the Icon A5 light sport amphibious aircraft.  It’s a neat design that can land on water or on a runway.  The high wing design with a pusher prop has foldable wings that allow it to be put on a trailer and towed behind a vehicle, allowing it to be offloaded at boat ramps (it also begs the question can you wakeboard behind it?).

Apparently, not all non-pilots know about the Icon A5.  Last week, one landed in the water near a beach in Southern California, but most of the beach goers and local authorities believed it had crash landed in the water.  Emergency crews were dispatched, but everyone was surprised when the two occupants crawled out on the wings, had a cup of coffee, and took back off.

You can read the full article on the Flying Magazine’s website.