Wednesday, November 30, 2011

Leg 4 - No ice for me, thanks

Time to head home, turkey and stuffing consumed, relatives visited.

Friday November 25th was a sunny day in Phoenix, high around 60, light to no wind.  I planned/hoped to take off around 9:30am, and tried to get everyone up and going on time, but to no avail.  We left the house in Mesa at 9:15, and got to CHD at 9:45.  I paid for the fuel and tie down, and taxied 40D over to the terminal at Chandler Air Service to load up.

The weather over the mountains of Southern Arizona and New Mexico was forecast to be scattered cloud, with showery rain from El Paso to mid central Texas.  Going back on V94, I expected that IFR I would be assigned 11,000 feet, and since Sally had shown some symptoms of altitude sickness at 11,000 on the way up, I decided to go VFR so I could fly at 9,500.  It also had the advantage that I could get out of the busy Phoenix area without worrying about terminal flow control and delayed IFR releases.

Bonanza's, like all high powered aircraft, can be difficult to start when the engine is hot.  This one was warm from the short taxi, and I wasn't sure which technique to use.  I decided to use the hot start technique, and start without priming, but to "goose" the electric pump as the started engaged.  This usually works well.......

The engine did not want to run.  It would fire, fire and stop.  Thinking that too little fuel was the problem, I tried again, running the pump longer, until another pilot came over waving his hands over his head, and told me that fuel was pouring out of the engine cowling.  The engine was flooded.  I shut everything down, we pushed the aircraft backwards away from the fuel puddle, and went to the Airport Cafe for a coffee while we waited for the spill to evaporate.

At 10:30, we loaded up again, and using the technique for a flooded start, I got the the engine running.  I called ground, and got taxi clearance to runway 22 Right, did my pre-flight checklist, and off we went, turning left to a course of 113, direct ITEMM.  I chose ITEMM as being a waypoint on V94 that avoided the military's airspace over the Superstition mountains, yet got onto the airway as far East as possible.

I had been watching a bank of clouds to the south East all morning.  As we drove to the airport, they were quite close, a solid overcast at what I estimated to be around 7,000 feet.  During all the faffing around at CHD, the clouds retreated southeastwards.  I assumed they would break up over the mountains, as forecast.  Now, as we turned towards the southeast, I could see that they were still a solid bank, but that we would be above them at 9,500.  VFR pilots can fly over a solid undercast of clouds, but it's wise to either know for sure that you can get down again visually somewhere ahead, or be instrument rated and have a backup plan.  I had both options available.

I called Phoenix departure and asked for VFR flight following, a halfway house where the pilot flies to VFR rules and must maintain VFR conditions (1,000 feet above, 500 feet below and 2,000 feet horizontally seperated for clouds, with 3 miles visibility), but communicates with air traffic control, who provide (on a time permitting basis) traffic reports and other assistance.  Initially, things were looking good.  The clouds topped at about 8,000 feet, and I reached ITEMM as planned, and turned toward SSO VOR.

The cloud tops kept rising, and eventually I realized I would not be able to maintain VFR.  I called ATC, and was given an IFR clearance along V94, direct SSO, direct DMN, direct EWM (Newman/El Pase) direct Pecos (PEQ).  Climb and maintain 11,000 feet (as expected), and squawk 1234.  I did so, and we cruised comfortably above the cloud base.  But it kept rising, and over Bassett Peak, we were solidly in the clouds.

"We're getting ice!" said Sally.  I looked at the wings, and said "I think it's just rain", but 30 seconds later I changed my mind, and called Albequque Center to tell them and ask for a climb to 12,000.  I got the climb right away, and Center asked me what the outside air temperature was and what type of ice.  I looked at the OAT gauge,and read back "1 degree", and not knowing much about ice (yes, I know I'm a CFI-I, but I'd never seen it for real), I said the first thing that came to mind "light rime ice".

It wasn't, and maybe center knew, because she asked me again.  I said the same thing, but I now know that rime doesn't form until 10 to 20 degrees below freezing, because once on the ground I looked it up.  This was clear ice, caused when supercooled droplets near +2 to -5 degrees hit the cold airframe and freeze on it.  Rime ice starts out already frozen, and looks milky.  The fantastic Bonanza climbed strongly to 12,000 (a new personal altitude record), where we leveled off in clear air, and the ice slowly sublimed away.  At this point I remembered to turn on my pitot heat, which should have been on before I entered any cloud at that temperature.  Learning experience!

After 5 or 10 minutes, the cloud tops reached 12,500, and we were back in clouds, with more icing.  Since we were now past the highest ground under the airway, I asked center for a lower altitude (I didn't want to go higher without oxygen, although the colder, denser air seemed quite breathable), and was assigned 9,000 feet, just as the clouds suddenly broke up and the tops fell way below us.  "40D would like to remain at 12,000 now, the cloud tops are below us".  "Bonanza 40D maintain 12,000 feet".  I asked for a clearance to deviate around the few remaining tops, and was cleared to deviate up to 30 degrees left, and right to no more than a heading of 100 degrees (to avoid the surveillance balloon near the border area with Mexico, I assume).

Just before reaching El Paso, the clouds started to break up, so I asked for 9,000 feet, and descended to pass over EWM (Newman/El Paso) VOR at 9,000.  On the Garmin 496 handheld GPS, the next challenge began to show ahead - patches of green representing light rain. ATC re-routed me over Salt Flats VOR (SFL), but that was pretty much on my direct path anyway, then they issued a heading direct Pecos, so I jumped ahead on the running flight plan on the Garmin 430W, and selected direct KPEQ.

Between us and Pecos were scattered showers, with clouds down to 6 or 7,000.  I asked for 7,000, and to deviate around weather, and was given unrestricted maneuvering - I suppose there was little other traffic on that US holiday.  After clearing the last shower and taking a few moderate bumps at maneuvering speed (130 kts in my Bonanza at gross weight), I cancelled IFR, and called Pecos unicom.  A soft female voice gave me the weather, and announced no other reported traffic.  I touched down on runway 09 at around 2pm, a nice 2.5 hr flight with an average ground speed over 200 mph.

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