Monday, May 16, 2011

Pearson Field video

USD Media produced this great video about historic Pearson Field, the fabulous facility that I fly out of.

Flight Ten: Best Glide & Power-off Landings

Todays emphasis was on best glide speed and performing power-off landings. This is a continuation of emergency procedures we began during Flight Eight. As Theresa is describing this in context...which is an engine failure...she starts relating things to how many more seconds in the air certain decisions give you...and in the back of my head I'm thinking "Oh man...shit just got real."

Best Glide Ratio
The Cessna 150 has a glide ratio of 1:7 - for every 1,000 feet of altitude lost you can glide for 7,000 feet or about a mile and a third. So if the engine dies at 1,000 feet you will be landing within that distance and you only have a few seconds to make the good decisions needed for that desired safe landing. Best glide for the C-150 is 70 MPH, which gives you the maximum lift for the least amount of drag. What's cool about this is you can trim the aircraft so that it descends at best glide with no hands on the yoke, giving you less to do while making your other time critical choices.

We headed out to the practice area and I performed a few landing configuration into a stall runs, first with power and flaps and then without either one. We jammed back to Pearson at 125 MPH and had time for three power-off landings.

Theresa did the first one to show me what to expect, however she came in a little too low and we aborted and went around. Then it was my turn and when I came around I was too high and I had to recover...that's when the unexpected (to me) happened. We were in a no power, best glide configuration meaning the trim was pitched way up but our nose is down. As soon as I added full power - the trim setting caused the planes nose to pitch up wildly. I had to push forward on the yoke really was a little scary...all I could think of for a second was this video. Theresa later told me, that's just how it is...and why in a real emergency, you shut-off the failed engine to ensure it doesn't suddenly restart while you are configured for best glide and just a few hundred feet in the air. Anyway, you just gotta muscle it out.

The final time around, killed the power, configured for best glide and turned towards the runway. Everything went really smoothly and I came in for a great landing, even if it was a little long and we had to taxi all the way to the end of the runway before we could exit.

Continuing with the Top Gun theme: "I feel the need...the need for best glide speed!"

Hours of flight logged this lesson: 1.1 Dual Received (DR)
Cost of this lesson: $143.11

Monday, May 9, 2011

Flight Nine: Patterns & Landings

The practice area north of Pearson field was socked in with clouds, but with a 4,000 ft ceiling over the field and low to moderate winds, we were able to spend the flight in the pattern and conduct 6 landings.

Having been three weeks since my last flight, I had lost some of the "feel" for the plane in flight and was not flying very smoothly at first and was very tense. This resulted in two flubbed landings, where Theresa needed to take over and land cause my approach was so off. The next two times around were not much better, but instead of taking over, Theresa had me perform the go-around maneuver. Now we've been up almost an hour and I had yet to land the plane by myself...and I'm feeling frustrated and nervous. So I willed myself to be calm and tried again.

The fifth attempt went great...set up went well, feeling in control the whole time, not too fast, not too high. A nice, main wheels first landing, on target and short enough to leave the runway at the first taxi way. We taxied around for one last take-off and landing in the pattern. Now that I had done something confidence was way up and the my final approach for the day was really good and the landing was even better than the previous attempt.

This is when the Top Gun sound track starts playing in my head "...highway to the danger zone!"

In our debrief, we concluded that it would be better (after a long break) for me to fly out of the pattern at least once after take-off, so I can get acclimatized to flying again, before jumping into complicated maneuvers like landing in the pattern.

Looking forward to getting up again next week.

Hours of flight logged this lesson: 1.2 Dual Received (DR)
Cost of this lesson: $149.81

Monday, April 25, 2011

Rained out...again.

My instructor just called to cancel todays flight. We had planned to just fly in the pattern around Pearson Field if the weather was poor, as long as conditions remained within VFR (cloud deck at 2000 feet AGL and visibility greater than 2 statute miles). No such luck today, visibility is down to 4 statute miles and falling this morning, and the winds will be picking up significantly by the time the visibility improves.

I was looking forward to making a whole lot of touch and go landings. I'm approximately halfway to my first solo attempt and I want to practice landing more than anything else. If I can get the weather to cooperate and get the hours in, I hope to solo by my birthday at the end of June. Between now and then we will practice landings and soon will go through some emergency procedures. Then, with a passed FAA medical examination in hand I will get a check ride from the head instructor at the field and they will determine if I'm ready to solo. If they say OK then...I'm flying and landing all by my does make me a bit nervous to think about it.

Monday, April 18, 2011

Flight Eight - Stalls, stalls, stalls...and more stalls.

It was a gorgeous day for flying today...sunshine and blue skies. Todays lesson was more of the same...slow flight, stalls and recovery. Being such a nice day there was a bit of traffic at the field, I guess everyone's getting in some stick time while they can. The new tower kept us apprised of other aircraft in our vicinity, we had a bit of a time locating another flyer that was in our vicinity as we were outbound over Vancouver Lake. Eventually we spotted him...just about 100 feet over the lake...crazy.

With nice clear weather, we were able to get to practicing right away...and I went through the routine of transitioning from level cruise to landing configuration. Carb. heat on, reduce throttle, add flaps, pitch down into decent profile - periodically adding more flaps, descending slowly, but not dropping below 80 knots or so...just above the virtual runway, level off, throttle to idle...and then flaring into a stall...feeling the controls get mushy, then the stall alarm horn goes off, the plane shudders slightly as lift spilled off of the wings impacts the tail...plane starts to sink...then it's carb. heat in, full throttle (trick is to stick out your thumb when pushing in the throttle so that it pushes in the carb. heat at the same time), raise flaps incrementally and start climbing out. Another Bald Eagle crossed our path today, but this time the eagle was much higher and further away than last time.

Theresa is really trying to get me to not grip the yoke too hard...something I still do when things change fast. So half way through our flight she had me weave a pen from my middle finger to my little finger of my left hand, leaving just my thumb and forefinger free to grip the worked.

After we had been up for just over an hour, we headed back for a one touch and go and then our final landing. There was even more traffic in the pattern on the way back and radio traffic was getting confusing to me. In fact as we made our final approach the second time around...the radio traffic got overwhelming and I got so discombobulated that I was not remembering to fly the airplane. Theresa jumped in and handled the radio traffic to help me get re-focused. The second landing was awesome (the first was pretty good too)...stalling warning sounding the instant before touchdown, hearing the little chirp of the main tires hitting and then bringing down the nose wheel for a smooth(ish) landing.

I'm now about half way to my first solo (usually happens between 12 and 15 hours)...I gotta go get that FAA medical exam soon so I'll be ready.

Hours logged: 1.3 Dual Received (DR)
Cost: $168.51

Monday, April 11, 2011

Flight Seven - Slow Flight and Stalls

A random Bald Eagle photo.
Not the one we saw today,
but this is the view we had.
Hooray! The weather finally cooperated this morning and my scheduled flight lesson actually happened as planned. Today we practiced slow flight and stall recovery as it applies to landings. Very similar to last lesson - the repetition of landing procedures is what were about for a while.

As of April 1, Pearson Field has been operating a temporary tower to improve separation from wake turbulence generated by commercial flights in and out of PDX. This changes the procedures slightly for departing and arriving. Theresa had me handling all the radio communications this time and it is starting to feel more natural. Check lists and taxiing went nice and smoothly this time (lot's of practice on the simulator pays off) and the take off was effortless.

We headed off the the practice area and did several slow decent to stall and recovery maneuvers and then returned to the field for a few touch and goes. Sometime during the practice runs a bald eagle flew right across our flight path, passing by on my side of the aircraft, we flew within 150 feet or was really beautiful. Damn, it feels good to be back in the air.

We had time for one touch & go and as we came around again we could see some rain approaching and Theresa had me land on the next approach. I landed both times by myself and according to Theresa...I was awesome.

If everything goes according to plan - I'm flying every Monday for the next 6 weeks if the weather cooperates and my funds hold out.

Hours of flight logged this lesson: 1.0 Dual Received (DR)
Cost of this lesson and new sectional map: $162.96

Thursday, March 10, 2011

A No-Fly Zone?

So February turned out to be a bust when it came to logging any flight hours. The weather would just not cooperate - my first scheduled flight (2/14  9:00am) was cancelled due to high winds. My second scheduled flight (2/28 9:00am) was rained out, but was hopefully pushed back until later that day. However, the overcast ceiling dropped down to 1,300 ft and it was a no go. The month of March was looking up, weather-wise, right until my car went in for some routine maintenance and ended up costing my entire flying budget for the month. Now my only hope for flying this month depends on whether or not my tax refund check arrives before the 31st. Oh well, here's looking forward to April.

Work and volunteer commitments, along with the remainder of Ground School (which just wrapped up a couple of weeks ago) has kept me too busy to keep up with this blog. I'm hoping to finish writing up the Ground School lessons (as much to keep this blog complete as for practice for my written exam) over the next few weeks. My plan is to take a lot of practice tests online and take the test for real in the fall. It's good for two years, meaning I'll need to get my private pilots license within two years of passing the written exam, otherwise I'll have to take the test again. Test will cost approximately $150 each time.

In the meantime, I now have a CH Flight Sim Yoke controller to go with my CH Pro Flight Pedals for use with my various flight simulators; the extra controls available make for a very realistic experience. Trimming the aircraft is much easier and it really makes a big difference in recreating the working environment of a Cessna cockpit. Another mod to the work station allows me to have my laptop handy to use for aviation maps - giving my instant access to all of the FAA Sectional maps as well as WAC (World Aeronautical Charts) and Terminal maps for the United States.

The last couple of weeks of Ground School covered navigation and how to use weight and balance tables - providing all the basic tools for VFR navigation and flight planning. Now I can use the simulator to combine practicing my check lists and basic flight maneuvers (landing mostly) with realistic navigation, and flight planning calculated with actual passenger and fuel loads. Creating virtual flights to local airports (at least those within range of a C-150) that will be practice for my own cross country solo flights that will happen towards the end of my flight training.

Monday, January 31, 2011

Flight Six - Patterns and Landing

N16221 in flight
The weather kind of cooperated this morning, and another flight lesson was possible (just barely). There was a low ceiling of clouds over the practice area and we had to fly out over the Cornelius Pass to find enough altitude for the practice maneuvers we wanted to attempt. My favorite practice plane, N704XA, has been sold and I flew for the first time in N16221 a 1972 C-150L that uses MPH instead of KTS for the airspeed indicator.

I got to the airfield early and performed the walk-around solo. I even found a problem with the nose gear and we taxied over to the maintenance shop to get more nitrogen pumped into the wheel strut prior to starting our run-up check list. It has been almost a month (27 days) since my last flight and it kinda showed...I had forgotten a few steps in the procedures and Theresa gave me some grief for not practicing the check lists more. I am hoping to start flying every other Monday for the next few months and will be doing more realistic practice on the simulator to keep my skill set current.

Once we reached a practice area with a high enough cloud ceiling, we climbed up to 3,000 ft. MSL and practiced the power changes and decent procedures in prep for a landing. Once I got the plane trimmed for level light at around 2,300 RPMs, started to cut power, first by turning on the carb. heat. Then, reducing power to 1,500 RPMs, letting the nose drop into a 500 feet per minute rate of descent. The aircraft is still traveling at 80-85 MPH and to drop speed, I begin to add 10 degrees of flaps. This causes more lift and the nose of the aircraft to pitch up - the secret here is to try and keep the same angle of attack. Once the aircraft settles down again, I add 10 more degrees of flaps, still maintaining the angle of attack. Finally I add full flaps and the aircrafts is still descending at 500 feet per minute and the IAS is down to 60 MPH. Finally I reduce the throttle to idle and the aircraft slows to just above stall speed. After each descent procedure we climbed back up to 3,000 MSL and tried it again. After a few tries, we headed back to the airfield to try a touch-and-go landing or two.

We approached Pearson from the NW and got into the approach pattern for runway 8. We went through the reduction of power and adding flaps and made our way to final - on the final approach, I did exactly what you're not supposed to do - I looked at the runway instead of a point out towards the horizon. I totally flubbed it. Theresa needed to take the controls to get us down...then it was flaps up, full throttle and we were up and coming around to the down wind leg of the pattern. This time as we came in on final - I had the right view point. We were a little off center and Theresa helped me get properly aligned to the runway. Then I had the controls and flared us to a gentle touchdown. My first landing!

In the debrief, we discussed how out of practice I had gotten on my procedures in the I need to practice more in the simulator so these things go smoother during flight lessons. I'll be back up in two weeks in the weather cooperates...hopefully, with more info. retention.

Ground school is just over half-way complete at this time. I have gotten a bit behind on writing up the class sessions on this blog. Lesson 5 is almost completed and I think I'll combine all of classes 6 thru 9 into a single longish post that covers all the lessons as they are the related topics of navigation charts and airports.

Monday, January 17, 2011

Ground School Class 4

Forces of Flight - Continued
Air is considered a fluid. Below speeds of Mach 0.3 it is considered an incompressible fluid. Static pressure plus dynamic pressure equals the total pressure which is expressed as:

Ps + Pd = Pt

Pd = 1/2(PV2)
where P = fluid density and V = fluid velocity

Newton's Laws of Motion (paraphrased)
  1. An object at rest, tends to stay at rest. An object in motion tends to stay in motion.
  2. Force equals mass times acceleration or F=MA
  3. Any action results in an equal and opposite reaction.
Bernoulli's Principle (paraphrased)
For an incompressible fluid, an increase in velocity will result in a decrease in pressure.

Magnus Effect (paraphrased)
Creation of dynamic pressure around a spinning cylinder in a fluid. Very similar to the way a wing generates lift.

Coanda Effect (paraphrased)
Fuilds will follow a curved surface. This is what helps to create the boundary layer of air over the wing.


L = CL(1/2)pV2A
CL = lift coefficient (calculated for each wing design)
p = air density
V = air velocity
A = wing area

Lift force occurs due to the creation of differential pressures above and below the wing. Lower pressure is created above and with the right configuration and speed, enough lifting force is generated to lift the weight of the aircraft.

The force vectors in a climb reduce the lift force and increase the induced drag. More thrust is needed to maintain a steady climb rate.

Wing Tip Vortices
All wings create wingtip vortices. The differential pressures that are created around the wing, collide at the wing tip and in doing so create a whirling of air that spirals down and away from the wing tips. This is a problem for planes that follow in the wake of other planes, especially during take-offs and landings.

High Lift Devices
High lift devices help create lift by changing the shape or the airflow over a wing. High lift devices are comprised of flaps and slats/slots. Slots are permanent holes thru the wing that allow high pressure air from underneath the wing to the top of the wing, helping to stabilize the boundry layer of air. Slats are slots with movable covers that are actuated under certain flight conditions.

Flaps are divided into four categories:

Plain - attached by a simple hinge, plain flaps change the curvature of the wing only.
Split - also attached by a simple hinge, split flaps drop from beneath the wing and increase drag as well as change the curvature of the wing.
Slotted - have a slot between the flap and the back of the wing.
Fowler - have a complex hinge that extends and lowers the flaps changing the curvature and increasing the area of the wing. Fowler flaps are what is outfitted on the C-150.

Ground Effect
Ground effect is caused by the wing vortices deflecting of of the ground and reducing the induced drag as a result. The effect generally occurs when the aircraft is within one/half wingspans length from the ground.

Positive Static - plane goes back to original flight path after you release controls.
Negative Static - plane does not go back to original flight path after you release controls.
Positive Dynamic - plane returns to flight path via a series of decreasing oscillations.
Negative Dynamic - diverges from original flight path via a series of increasing oscillations.

Three Axis of Flight
There are three axis of flight that each rotate around the center of gravity of the aircraft.

  1. Pitch - lateral
  2. Roll - longitudinal
  3. Yaw - vertical
Center of Gravity
All aircraft have a center of gravity (CG) envelope. When the plane is loaded for flight, the center of gravity must fall within the envelope for the plane to fly safely. If your CG is too far forward:
  1. aircraft nose will be heavy
  2. needs a longer take-off roll
  3. higher stall speed
  4. more stable
  5. may not be enough elevator to raise nose
If your CG is too far aft:
  1. aircraft tail will be heavy
  2. unstable in pitch
  3. elevator is less effective
Lateral Stability
One way that aircraft maintain lateral stability is by mounting the wings in a dihedral configuration. This means the wings are mounted in a shallow V. This adds lift to the forward wing in a side-slip - correcting the side-slip automatically.

Stalls always occur when the critical angle of attack is exceeded, usually around 18 degrees. Usual recovery is to simply lower the nose.
  1. Power On - usually during take-off
  2. Power Off - usually during landing
  3. Accelerated 
  4. Cross-controlled
  5. Secondary - too aggressive a stall recovery that results in a second stall
Next class: Spins and Flight Operations.

Tuesday, January 11, 2011

Ground School Class 3

Altimeter Gauge
Attached to the static air port, a sealed bladder inside the altimeter gauge inflates and deflates with changes in air pressure. The changes in size are transfered via a series of gears and levers to drive the gauge needle. A small dial and window allows for the setting of the current barometric pressure so the instrument reads the correct distance to the ground.

There are several types of altitude:

Indicated - altitude above sea level.
Pressure - 29.92 inches of mercury is the standard datum.
Density - pressure corrected for non-standard temp.
True (MSL) - Above Mean Sea Level.
Absolute (AGL) - Above Ground Level.

The allowable altimeter error for ILR flight is 75ft. Any greater error and the aircraft is no longer legal to fly.

The altimeter needs adjustment every so often (every 100 miles or so) to account for the changes in atmospheric pressure. This is especially important when traversing from high pressure to low pressure or from high to low temperature. As the pressure or temp drops the un-adjusted altimeter starts to show an increase in altitude, causing a correction that is descending rather than maintaining level flight.

There are a few ways to make the altimeter adjustments. The radio is the most common - as you pass near different airports, you can listen in to their ASOS or other automated weather broadcasts that will state the current barometric readings for the area.

Vertical Speed Indicator
Vertical Speed Indicator
Also connected to the static port, the VSI indicates the aircrafts rate of climb or descent in feet per minute. The trend is always accurate; if the needle shows accent, you're climbing, if ti shows descent, you're descending. However the rate indicated has some lag and takes a few seconds to settle down and provide and accurate reading.

Gyroscopic Instruments
These instruments use gyroscopes and the principle of rigidity in space, as the aircraft essentially rotates around the instruments. Gyros are either electric or vacuum powered.

Attitude Indicator
Attitude Indicator
The attitude indicator is also known as the eight ball. It show the pitch and roll of the aircraft in a single reading. The attitude indicator uses a vacuum powered gyroscope.

Directional Gyroscope
Directional Gyro
The directional gyro is just a stabilized compass. It needs to be adjusted via the magnetic compass every 15 minutes in order to remain accurate.

Turn Coordinator
Turn Coordinator
The turn coordinator uses the combination of an electric gyroscope and gravity to help the pilot make good coordinated turns using just the right amount of rudder.

"Whiskey Compass"
Magnetic Instruments
This means the regular compass or "whiskey" compass. It's just a ball floating in liquid, so the compass is hard to read in flight due to it's bouncing around all the time. The instrument has mass and is affected by acceleration, deceleration when traveling east or west and leads or lags turns when traveling north or south. The compass reads magnetic north and all navigation charts are based on true north. Our sectional charts provide the information to calculate a heading correction. An isogonic line follows the curve of the earths magnetic field. The difference between the isogonic line reading and true north is used to correct your navigation heading.

Forces of Flight
There are four forces of flight:

  1. Lift
  2. Thrust
  3. Weight (Gravity)
  4. Drag
When in level, non-accelerated flight, all four forces are in equilibrium.

Lift & Wings
Lift is generated by the wings. The wing elements are the leading edge, trailing edge, camber and the chord-line. The chord-line is an imaginary line drawn straight between the center of the leading edge and the center of the trailing edge. The angle of incidence is the angle that the wings are attached to the fuselage. The angle of attack is the angle between the chord-line and the relative wind. The wing will always stall at the same angle of attack, regardless of air speed.