Friday, December 7, 2012

Deer changes plans: Transition to Complex

After a brand new engine in the Diamond,  things looked good.  30 hours into the break in period, there was still an odd differential in EGT for cylinder one.  The last I heard concerning this issue is identification of a missing seal.  I was getting excited for a VFR night flight to fulfill another commercial requirement.  Four days before the flight, another club member had an unfortunate mishap with a deer during a night landing.  The front nose wheel strut was damaged.  Everything else looked ok.  However, the prop did make a mess of the deer.  If I get a chance, I will post some pictures.  Not pretty.  To be conservative, the engine is going to be stripped down and reinspected for an internal damage.

I decided to minimize my down time and begin the transition to complex aircraft.  This work is applicable to the ten hours of complex training required for commercial certification.  If all goes well, I should be flying a Piper Arrow PA-28r-200.  I like to be prepared for such adventures.  I downloaded a POH for the aircraft and began my studies.  Naturally, my focus is on the gear operation.  Many of the other procedures are not that different from the Diamond.

The Arrow has a hydraulic gear system.  It uses pressure membranes to control operations.   One nice property of the system is an automatic gear release when the aircraft slows below 105 with less than 14.5 inches of manifold pressure.  Furthermore,  the gear cannot be retracted at air speeds less than 85 knots.   The speed of gear down operations actually varies between 85 and 105 depending on power and altitude.  This brings about two questions: (1) How does one practice stalls and chandelles with out the automatic lowering of the gear and (2) how does one retract the gear early when necessary in certain a short field take-off settings when speed is below 85 knots?  The answer is the same for both.  There is a manual gear level between the seats that has an 'override' by pulling the lever up.  The level also serves in a preliminary step to force a gear down when the gear switch result in a gear release.  There is a latch to hold the lever in the up position.  Naturally, this should be temporary to avoid overriding the safety feature.

The lever is accompanied by a blinking warning light that is operational in situations where the gear switch disagrees with the situation of the airplane.  For example, a gear up when the plane is on the ground or manifold pressure is below 14 inches, or when the override lever is engaged.  The plane is accompanied by a gear horn.  The lights and the horn are electrical.

Lowering the level to floor is used to release the gear.  It used when the gear switch fails to lower the gear, normally indicated by the absence of three lit green lights.

The gear can be lowered at or below 125 IAS.  A normal approach includes a gear down prior to final, lowered as part of the pre-landing checklist.  Final approach speed is no less than 90 knots to the flare.  I have not looked at the performance charts in great detail to recall the specific speed variations according to weight.

Raising the gear naturally occurs after establishing a stable climb at or above 85 knots.    Normal climb speed is 95 knots gear down and 100 knots gear up.

Other interesting properties of the Arrow that stood out at first read are as follows.
  • The Stall Horn is electric
  • Panel should be dim during the day to not mask the gear lights.
  • The systems 14 volts, not 28 like the C172.
  • The Arrow is accompanied by a secondary vacuum system.
  • High altitude operations affect the gear system due to the pressure sensors.   This does have implications in high altitude airports. 
  • The hand brake use the same brake fluid reservoir as the toe brakes.  
If all things go according to plan including weather and a healthy Arrow, I will be have my first flight tomorrow.   I plan on writing up any misconceptions and new lessons in my next blog entry.  In addition, I plan on doing a performance comparison.  From what I understand, flying the Arrow is not as sensitive as the Diamond.  Flying the Diamond requires very little stick pressure, even on the flare.   Consider that a flare and landing with a C172 ends with the wheels touching the ground when the yoke is back as far as it can go.

Wednesday, November 21, 2012

Commercial Pilot Performance Considerations

I started working towards my commercial ticket.  Naturally, every time I fly, I build hours towards the 250 minimum.  Like private and instrument pursuits, the initial declaration of intent followed by a concrete plan helps focus on the goal.    I plan on completing all cross-country requirements by the end of this year.

The critical elements of the commercial certification include complete understanding of aircraft systems and proficiency in aircraft control, maximizing performance.  As part of meeting first goal, I have am fortunate to be flying the Diamond DA 40.  It may not have a retractable landing gear, but there is plenty of opportunity to understand power and efficiency with respect to controllable pitch prop and engine.   The second goal is met through a series of maneuvers, including chandelles and the 180 degree power-off landing. 

The rest of this entry focuses on performance.  I put all this together from my first flight applicable to the twenty hours of dual flight commercial requirements.  The flight consisted of a two hour minimum VFR cross country flight to an airport greater than 100 NM straight line distance from the departing airport.  I chose to fly down to Lynchburg, then to Greenbriar (WV) for the local eatery’s famous pulled-pork sandwich and then back to Leesburg.    All my long flights as of late have been IFR.  The VFR flight was a joy and I picked a great day to do it.

Although the flight discussions included review of flight planning (NOTAMs, weather, runways, fuel management, weight and balance), much of the time was spent discussing performance.    I was reminded how critical weight and fuel planning go hand in hand.  All airline pilots KNOW landing weight, with consideration for fuel burn.  Landing weight allows the pilots to optimally choose the slowest approach and landing speed.  Recall that higher weight raises the stall speed and requires a faster approach.  A faster approach means a longer landing roll.    Comparing this landing roll to runway distance requirements is critical to prevent over-runs and failure to comply with LAHSOs.   Talking with Mooney pilots, I began realize how critical weight calculations are to their every-day operation.   Mooneys have a bad reputation with newly minted private pilots.  Why?  Basically, they are not as forgiving of improper weight/speed management.  Of the two Mooney pilots I know, they both have handy little weight/approach speed ratio charts.  They watch and record fuel flow regularly through the flight and ‘double’ check indicated fuel with expected fuel (roughly fuel flow per time * time elapsed).  

I am leaving out consideration of wind speed and temperature since the calculation determines indicated air speed.  Ground speed and true air speed factor in the landing roll distance calculations, as provided in any POH.  Higher temperatures result in higher true air speed and ground speed (not indicated air speed).  Wind does the reverse.   As a private pilot, these calculations are typically done in pre-flight.  A private pilot is not usually tested on calculation updates while flying.  However, from what I gather from hanger talk, air transport pilots use flight computers to due the math as part of the landing checklist.

Engine Performance

The new engine in the Diamond presented a good opportunity to learn about the systems.    The first 50 hours of a new 180 HP engine is critical break-in period.   Most of the running time is at 75% power (135 HP) for longer durations.   It is not the time to do pattern work!   One of the interesting challenges has been diagnosing a 60 degree  (F) spread in cylinder head temperatures between the four cylinders.   This maybe more common with normally aspirated carbureted engines.  Prior to the engine replacement, the spread was closer to 30 degrees in the fuel injected Lycoming IO-360.  Cylinder one has been running hot.   Running 100 degrees rich of peak (ROP) has resulted in higher fuel burn and considerably cooler cylinders two, three, and four.   Even leaning and enriching slowly to allow the temperatures to stabilize after each adjustment has yielded the same consistent results.    A big spread indicates that the cylinders are not supplying the same amount of power.  Such an in-balance may result in roughness.  

What could be causing cylinder one to run hot.  A couple of ideas include
(1)  Fuel intake port nozzle issue resulting in less fuel being injected into the cylinder one thus making the hot cylinder leaner than the rest.
(2) An air flow irregularity used the injector to regulate fuel force (the fuel pressure differential)
(3) Baffling and cowl airflow inconsistencies resulting inconsistent cooling.

Since the engine has been running smoothly and playing with nozzle inspection did not yield any identifiable issues, idea number three seems likely.  The POH is the guide to achieving 75% power.    A standard atmospheric temperature, the Diamond runs 75% power at 500 feet with 24.1 inches of manifold pressure and 2400 prop RPM. Over 6000, the 75% power is not achievable according to the POH.  For example, at 8000 feet with full throttle (which is where I keep it), the manifold pressure is under 24 inches (closer to 22) and the fuel flow is roughly 9.8 GPH. 

Empirical studies demonstrate operations at either LOP or ROP with the IO-360 results in lower cylinder head temperatures.  In fact, the graph of CHT with respect to Fuel Flow looks like a mountain with the peak at peak EGT (and CHT).     Next time I fly up, I may try a LOP operation of cylinder one.  What I expect to see is that one of the other three cylinders SHOULD get hotter, as it would be closer to the peak EGT.  If this is the case, then perhaps ideas 1 or 2 are applicable.

As a commercial student, knowledge of turbo-charged engines seems appropriate, although not required.   I will not be working with a turbo-charged engine at anytime in my commercial training.  Turbo-charged engines require close monitoring of engine temperature.  Lycoming TIO-360 engine turbine inlet temperature (TIT) should not exceed 1650 degrees Fahrenheit.   Turbochargers use exhaust gases to propel a turbine to compress and pressurize air flowing into the manifold. In some engines, automatic control of exhaust gas into the charger allows the pilot to following similar guidelines to RPM and mixture control as with non-turbo charged engines.  The only change is diverted focus on TIT instead of EGT.   Other systems use a manual waste gate control to control to diversion of exhaust gas into turbocharger inlet.     A closed waste gate at low altitude can push manifold pressure to unsafe levels.  Thus, monitoring manifold pressure is a critical component of these ‘manual’ systems.  Automatic waste gate systems are typically controlled by oil pressure.    Oil pressure opposes a spring to close the waste gate, increasing intake pressure.    As expected, an increase in throttle increases oil pressure, thus closing the gate, resulting in MORE power.  A pressure relief valve protects the system of over boosting.  With automatic oil driven systems, the engines must be sufficiently warmed up prior to full power application in order to guarantee adequate pressure for full power.  I have heard of other types of pressure regulated chargers applying some sort differential pressure system with manifold and exhaust pressures.   The two pressures run hand in hand.  Lower manifold pressures indirectly affects the exhaust pressures, causing turbo charger adjustments.  The end result is a perpetual fluctuation, which is inefficient, causes frequent temperature changes and occupies pilots attention.

My next flight is a 2 hour night VFR flight.  I enjoy flying at night.  I went out for a quick flight the other night to work on holds and approaches.  In the fall, the cool air is smooth.   I started to work on the chandelle maneuver.  My first observation is that the speed drops off very quickly. However, optimal altitude gain is not achieved unless continuous increase of back pressure is applied.  I stopped short before continuing back pressure. When I completed the turn, I still had 10 to 15 knots of useable speed. 

Sunday, July 29, 2012

Back to Basics: VOR Approaches

I have been playing around with the Garmin 530 for a few months now.  Most of the approaches I have been practicing include RNAV or ILS approaches.  I decided it is time to go back and review my VOR skills.  I am glag I did because I was extremely rusty.

I chose the Martinsburg (KMRB) VOR approach shown below.

The key thing to note about the VOR hold on the approach plate is that it is left turns.  

From my south westerly heading, I entered the VOR hold using a direct entry.  My first entry just sucked.  I did not start my out bound timer when the flag flipped (on the 109 heading), so after about a minute a swung around and tried again.  The second time I nailed it.  However, I started descending before the flag flipped to FROM on the 289 heading.  Once again, I missed the timer.  I went missed on the approach to try a third time.  This time, since I was on a missed approach, flying roughly a 80 degree heading, I entered a tear drop turning 139 degrees after passing over the VOR.  Technically, a parallel entry would have been appropriate.  However, my late instructor John Crouse stated that the tear drop hold is better suited for approaches if possible.  Do not question John.  He has more experience than 90% of the pilots out there.

Finally, I executed the VOR approach without error.    On a tear drop entry, it is not necessary to go around the track one more time.  I performed the full hold to get my speed set and settle into the approach.  

  • One thing that stuck in my mind after completing the exercise is how I need to start using the acronym "turn twist time throttle talk".  Turn on the hold pattern.
  • Twist the OBS to the appropriate heading if necessary.
  • Time ONCE the flag flips (crossing back to the outbound heading).
  • Adjust throttle for the approach.
  • Communicate with ATC that your are holding, giving the altitude and location.  For holds outside of an approach, the direction of the hold is recommended.
Communication was critical this night as the traffic around MRB was moderate.  It was a pleasant night to fly and I was not the only pilot out there using MRB.

Another take away: I need to setup my home simulator to practice more often.  

JYO to HSP for some hiking

I decided to take my son on a little excursion to Hot Springs for some hiking.  The airport is on top of a mountain.  I have passed by the airport quite a few times and thought it would be fun to explore the nearby landscape.

The flight there and back was routine.  I flew VFR both directions.  I still kept the GPS programmed with the plan and flew direct, making the navigation easy.  I decided to take the time to refine some of the skills that I have not been especially good at using since the introduction of the GPS after obtaining by Instrument certification. Specifically, using VORs to track my progress and add to situational awareness along with VFR skills of following the sectional.   As a coincidence, the following post from the Pilot Workshops came the same:

Here are some simple things to do.
  • Use the GPS to find the nearest or next VOR along the route the plane is tracking, punch it into the NAV frequency to always have the frequency ready if GPS goes down.
  • Always IDENT the VOR.  Keep this practice.  If flying a GPS approach in lieu of a localizer or VOR, then have the VOR or Localizer frequency in Nav radio and idented, even if not used for navigation.
  • Keep the sectional ready and open to the segment of flight.  This does not mean that one should follow it closely as some pilots suggest.  The GPS can still serve this function.  However, keeping the page open and the fold of the page on available to viewable for the region the plane is tracking removes the struggle.  I have not been doing this.  I do have the chart handy and I track with my IPad.  The digital approach is nice since it reduces the workload, provides a nice backup, and permits easy flipping between section and IFR enroute charts.
  • I spent some time looking up some of the FSS frequencies in the area.  There were some TS in the vicinity of the areas of flying.  I did not come close to any.  My flight conditions were VFR.  However, I wanted to have the FSS frequencies with me if I needed to file  IFR if the cloud front were to move in front of me. 
  • I did get call Flight Watch enroute to make sure I was not running into a small pocket of storms.
These are all simple things.  However, I do not believe in idle time flying.  There is always something that can be done to keep one two or three steps ahead.   Practicing these actions increases the comfort and efficiency of the techniques, working them into a routine.   My late instructor, John Crouse, never let me have an idle moment.   He wanted me to always be looking at what is next on the list to do (radios, review of approach charts, mixture adjustments, performance and fuel checks, time checks, etc. and any thing else that can keep me ahead.

Hot Springs (Engalls) is a nice little airport on top of a mountain.  The runway is sufficiently long.  Landing distance on this particular day was not an issue.   I chose HSP since it is supposed to have some hiking trails off the airport.  The trails are there, but they are short and barely interesting.  Still, my son and I made the best of the situation.  We went looking for bears and rattle snakes that frequent the airport.  We climbed up an very old water tower.  We then rummaged through an old house (aka trespassing) looking for anything really old.  We did not find anything.  The house was filled with taxi way lights.  Not interesting or old.  The taxi lights are big green bodies with blue plastic hoods. 

We did have one special treat.  A couple of Osprey on a training mission landed on the runway while we were hanging around the field.  The approach of the Osprey was interesting.  They approached the airport side by side. Then one slid behind the other to land nearly simultaneously.

Wednesday, June 6, 2012

From VA to CT and back again in the DA-40.

Just finished a trip to CT from VA using the Diamond DA-40. JYO to IJD.

This was my first long cross country IFR by myself since I earned by Instrument certification. As one can expect, I made some mistakes, learning a few things a long the way.

I requested simple track: FDK and then direct at 9000. ATC cleared for STILL MRB HGR LHY CMK Direct. Although, on route, there were changes. A couple of times, I studied and request a more direct route. ATC granted me each request only to have it readjusted after a hand off. My actual route flight took me farther north than optimal. My last waypoint was the HFD VOR.

Looking at the map below, there is one small deviation at the elbow coming out of VA to head east. This occurred while I was tracking to figure out why the Auto Pilot (AP) did not make the turn. It was set to Navigate and hold altitude. I do not recall how I went wrong there, but it was easy to fix. I put the AP back to ROL and heading mode, using the heading bug to set the new course and then I set AP back in NAV mode to initiate once intercepting the correct course.

The other disappointing deviation is the two altitude bumps. I realized that it best to change the descent rate, as recommended by the AP guide, as the plane nears its target altitude. For example, I can set the descent rate to 500 FPM, and then adjust to 100 FPM as I get near the altitude. If not, the AP tends to ‘overshoot’; ‘undershoot’ in this case;-) This is obvious from the altitude profile on my descent. The other little bumps were changes in pressure as the flight progressed. The general pressure trend was high to low.

The little bumps in the altitude graph seen at the beginning of the flight were caused by me playing with the AP’s altitude options.

The biggest mistake on this trip was not studying the POH of the aircraft in sufficient detail. I plan on remedying this soon. The condensed checklist for the aircraft is simply not sufficient. There are two critical notes in the POH that I should have seen and noted. I copied them below for reference.

While switching from one tank to the other, the electrical fuel pump should be switched ON.

When the fuel pressure warning light illuminates, or the fuel pressure indication is below the green sector, the electrical fuel pump must be switched ON.

The ‘CAUTION’ is obvious to me. The actions I took are consistent with the CAUTION. I switched the tanks at 9000 feet and then, around ten minutes later, I started seeing erratic flow issues. The fuel pressure light indicator was not lit, nor was the pressure remarkable. I knew that I missed something. At the time, rather than dive into studying the POH, I switch back to other tank while I pondered what was going on; I realized quickly that the fuel pump was necessary in this case. Had I reviewed the POH more thoroughly, I would have been aware of this. I had spent time before the flight reviewing the emergency procedures and electrical system, skipping over normal procedures because of my handy little condensed checklists.

Things I did well on this flight included good communication with ATC, better preparation and understanding of the AP, and relentless note recording along the entire flight. My flight log consisted of times associated with each frequency, altitude, and course adjustment along with issues and discoveries. I became my own little flight recorder.

I landed at Windham airport, which is very close to my parent’s house. The problem with Windham is the FBO is temporarily closed, as indicated by this NOTAM: IJD 05/003 IJD SVC FUEL NOT AVBL. I found a tie down and then talked to some of the locals about the best place to get fuel. They recommended Danielson for affordable fuel. Very friendly people at Windham! I learned that the diner up on the hill near the airport has a nice place to relax and get a good meal. I did not stop by but it seemed to be a popular place. Another time.

My plan on the return flight was to head over to Danielson VFR, fuel up and file IFR back to JYO. I filed plan I found from the recently/frequently used plans from The plan a filed was HFD V3 MXE V419 EMI V3 RUANE . When filing my plan, I requested from FSS confirmation of the departure clearance phone number since I was unlikely to get DC on the field. AOPA’s airport information provides a number for Bradley. FSS gave me a Providence number. At Danielson, I called the number. Unfortunately, I did not get an answer. I called FSS back and they gave me another number. Again, no luck. Here is where my mistake occurred. I grew a bit impatient and figured I would start out on my proposed plan at VFR altitudes and pick up Providence from the air. I had VFR conditions below 3500. However, this did not go as planned. I had no luck getting Providence on several different frequencies. I did get a hold of Providence Approach briefly, but the signal was poor so they referred me to Boston. I called Boston and they referred me to Bradley. After the shuffle around, I was well on my way and started to look for a nearby airport to land and file a new plan; start over! I mentioned this to one of Bradley controllers. She said stand by; I could continue on course as long as I can stay VFR. After what seemed like a very long time, Bradley got back with me, directing me New York. New York got me on my way. The only issue at this point was I had to swing back to Groton. This debacle added unnecessary workload for both me and ATC, burned excess fuel, and added unnecessary flight time. Never again. The cleared flight plan was ORW V16 JFK V16 ENO V268 BAL V214 MRB.

I learned, through my research and some hints from my flight instructor, that I can look up the plan that I am likely to be cleared using, provided I file early enough. If I recall correctly, the plan is available roughly 30 minutes after filed, but I advise checking close to the departure time, as things do change. This tool can aid the clearance instruction exchange with ATC.

The rest of the flight was fairly uninteresting. At one point, there was a little confusion between myself an ATC. They made some adjustments in my flight in route. At one time they gave me DIXIE. I first entered DIXEE in the GPS. I could have sworn they said ‘Delta’ ‘India’ ‘X-ray’ ‘Echo’ ‘Echo’. I probably misheard it. I started on course to DIXEE and felt that the direction was wrong so I called back and got confirmation. All other adjustments provided by ATC were clear.

In the future, I am going to spend more time studying the different routes assigned by ATC along this route using both and I want to be more familiar with the airways and waypoints, rather than trying to discover them during the flight using IFR Low Enroute charts.

I applied some stick and rudder skills through clouds at the beginning of the flight, avoiding some of the more ominous ones while getting bounced around a bit and enduring the fluctuations in pressure and temperature. I eventually turned the AP on, letting it handle the more boring aspects of the trip, allowing me to focus on navigation and systems.

Saturday, January 14, 2012

Transition to Diamond DA-40

After training almost exclusively with a Cessna 172 Model N, I am now transitioning to a model Diamond DA-40. I have had the opportunity to fly 172 SPs. The 172 SP has basically the same engine as a DA-40 (Fuel Injected Lycoming 180 HP). So, there is some overlap on the procedures. However, the SP, M and N models have every similar flight characteristics. The Diamond is a bit different. This blog entry describes those differences that stood out for me.

As one would expect with a low wing, the landing roll is longer, as the plane enters and stays in ground effect longer. The wing span of the Diamond is greater than the Cessna 172. With lower wing loading, the take-off, climb an turning performance of the DA-40 is superior to the 172 SP. On the flip side, the 172 SP feels more stable in wind gusts. In the DA-40, I did feel more like a feather than within the 172.

The DA-40 has T tail. Flying with a T tail had only on significance to me in standard flying conditions. In a 172, the air movement from the prop wraps around the plan and interacts directly with the horizontal stabilizer. A drop in power results in a fairly pronounced drop in the nose. In the DA-40, I found this effect less pronounced. Please note that T tails have a disadvantage in slow turns, as disruptions from a stalled wind reduce the flow over the tail, deepening the stall.

I have heard that cross wind landings are more difficult in the DA-40, in part due to the low wing, reducing the amount of aileron that can be used in the flare and, more importantly, a small rudder. I am not convinced on the last part. For a test pilot, this may be true. For myself, I did not notice any less effectiveness in cross wind landings than the 172. Those wind conditions that test the plane's performance (about 15 its cross wind component) are outside the conditions I willing to try in either machine.

To get a sense of the transition to a DA-40, I am going to start at the ramp and walk through key parts of the check-list that are different and significant. I am picking only parts of the check-list thats meet this criteria.

On the ramp during the pre-walk around, I switched on the battery. I noticed that, given a few seconds, the engine instruments give me a more accurate reading from the digital display. I can get oil temperature and CHT. This is great in the winter to get an idea if preheating is necessary. The fuel indicators seem fairly accurate. It is a bit harder to judge the fuel visually since the tank filling ports are higher on the wing. After flying for over an hour, the gas will not be visible on a flat ramp. When lowering the flaps, I noticed they are tiny. There only two notches of flaps. I could not tell what the degrees are from the panel. My guess would be something like 10% and 30%. On inspection of the flaps, I though that the effect of the flaps on a T tail may be a different, with less disruption of air flow over the horizontal stabilizer. The battery is on, I noticed may of the instruments were working such as the attitude indicator. Why? Because the attitude and compass (HSI) are electrically powered. The 172 uses a vacuum pump powered from the engine.

The start up procedures are similar to the SP. The ammeter is not turned on until after engine start and engine instruments are in the green. It is best to pull the mixture a bit after start to prevent fowling of the plugs during taxi.

Taxiing the DA-40 is a more of a challenge than a 172 due to the free-castering nose wheel. Gentle tapping of breaks to handle direction changes is necessary for control in many situations.

At run up, the prop needs to checked. Pull the prop gently all the way back and then push it forward quickly. You do not need to wait for an oil pressure change. The change will show during the push forward to 2700 RPM. If it does't, try it a couple of more times to get the oil moving through the prop governor.

Before take-off, the fuel pump is turned on, on notch flap is added. Mixture and prop are full forward (low altitude). Take-off is easy and quick. If there is a bit of shake during the latter stages of the take-off roll, the nose wheel is has gaining too pressure so pull back (slightly). The Da-40 accelerates quickly. Watch the airspeed and hold the plan in a climb at around 80 kts. The DA-40 climbs very quickly. Once in a positive climb, bring up flaps, then adjusts prop to 2400 and, once safely above the 'deadly turn; height, shut off the fuel pump.

Watch the Engine temperate. At low altitudes, the DA-40 moves. I am always in the yellow arc when leveling off at low altitudes. So, it makes sense, at low altitudes, to adjust the manifold pressure to 24 inches.

Once in level flight, adjust the mixture. Switch the to EGT and pull back the mixture slowing until one of the CHTs flashes. Then notch forward on the mixture until the hottest cylinder is about 1400. I noticed in level flight, trimmed for cruise, the DA-40 has a nose-down attitude in comparison to the 172. I loved the visibility. Speaking of nose down attitude. Check out the two passenger weight balance for a DA-40 with full fuel. This places the plane near the forward CG line. This means there is less 'room' to pitch up before approaching the 16 degree angle of attack.

I practiced stalls in the DA-40. It feels just as stable as a 172 to me. Recovery is quick and easy. The DA-40 throttle and controls are extremely sensitive. I need a light touch to make adjustments. Trimming is a piece of cache with the trim control on the stick. I still like the trim wheel!

In descents, a little more planning is required. Slowing down the DA-40 for the pattern takes a little more time. I keep the prop at 2400 RPM and ease back the manifold pressure to 18 inches. When in the pattern, I hold the plane at 100 kts until abeam of the numbers, then I apply one notch of flaps. Then, I pull back to about 15 inches and start my turning descent. On final, fuel pump is turned on, mixture full rich, prop full forward, and the landing light on. I adjust the manifold pressure to about 11 inches. Once landing is assured, I lower the flaps (second notch) and begin brining the power back. It is critical to keep the speed above 70 kts. The stall speed of the DA-40 is not as advertised. Once level with the runway in the flare, just pull back really slowly to slow down the plane. It settles nicely. Do NOT let the nose drop, as the nose wheel is not as forgiving as a 172. Aggressive pulling on the stick is not necessary. A slow steady pull keeping the nose slightly high is sufficient. Too much pull causes tail strike or, even worse, a premature stall above the runway, causing a bounce. If this happens, apply power, holding the stick steady. The plane will begin settle again.

Through out the process, I realized that the work load of the DA-40 is a bit more than the 172 models. That's fine by me. It moves me closer to the load of an RG and proficiency requirements for a commercial rating. In the end, the most important element is the ability to fly the plane. Of this, I have no doubts that I can handle the DA-40. Out of 5 landings so far, two were smooth and gentle. The other three were a little rough.

Monday, November 15, 2010

Preparing for tomorrow's lesson

Tomorrow's forecast fro MRB and HEF is overcast at 700 with 2 SM rain. This above minimums. I just have to remember the following:

(1) When getting a clearance, fly the airplane first. Then communicate.

(2) When doing the hold for the approach into MRB ILS 26, I do not need to go around. Just use a tear drop to get established. Always use a tear drop for an ILS. Do not use the parallel entry as this may force you to fly around one more time to get a full minute.

(3) If using a VOR approach, the speed has to be set at station passage so the clock can start and be measured accurately. Waiting till station passage to get the speed correct will throw off the ETA estimates. After station passage, set up for a 800 FPM descent to the MDA.

(4) Always right down frequency, altitude and time changes! This is critical when flying VFR-on-top or flying on a cruising clearance.

(5) On a missed approach, declare to tower, get set up, then contact DEPARTURE with what you want to do next!

Thats it for now.

Sunday, September 26, 2010

First IFR Flight: HEF to MRB and back again


The training plan was to use the full ILS approach into MRB for ILS 26. This approach involves passing over the MRB VORTAC. From the north, a flight can follow R-126 off HGR to intercept the localizer. The MRB transition involves a fly-over of MRB, followed by an outbound heading on R-053 to intercept the localizer. At that point, a mandatory hold to get from 4000 down to 3400 for the glide slope interception. This requires a parallel entry into the hold. I chose a tear drop, applying a 110 degree magnetic heading away from the intersection point to loop back into the hold. Since that takes about a minute and half to do that, loosing the 600 ft is trivial. Still, a hold is a hold, not procedure turn. I completed one full hold to insure proper glide slope interception.

Given a clearance for the approach I was informed to contact tower at HEVEN. This requires configuring the second VOR MRB R-353. To intercept the glide slope, the second VOR was set to MRB R-053. Sometime during the hold, this needed to be adjusted.

We did not land, instead using the missing approached as a training tool. Once missed, the tower immediately asks for intentions. Always have the backup plan ready. Since MRB is still in the second VOR (and probably the standby of the primary), no additional frequencies changes were needed. I informed tower I wish to complete the missed approach and then activate the flight plan to return the Manassas.

Once on course for Manassas, I began to get overwhelmed: too much information. I began missing altitude and frequency changes. The concept is easy. I was to get vectored back to Manassas. Without vectors, I would need to intercept V4-92 West of MANNE on the ARML VOR, proceed on the airway till MANNE (11 DME) and then proceed for 1.2 miles and then turn left to heading 163 to pick up the localizer for 16L at Manassas. However, this will never happen I always get vectored into DORGE intersection.

Things I learned:

  • Always write down the frequency changes and altitude changes. Keep a list to know what the last frequency if needed.

  • Listen carefully.

  • If you do not have ATIS when requested (such as the activation of the flight plan back Manassas after the the Missed Approach), then say 'Will Call Back when I have information from ATIS'.

  • On call back for a clearance delivery, listen for key words like Transition. I never got the MRB transition requested on the HEF to MRB flight plan. I was told to 'expect vectors to Martinsburg after Casanova'.

  • Listen for the word 'heading' vs. 'radial'. They are not the same.

  • Phraseology.

    Filing Plan: "Requesting 4000, ASRLN2.MRB TRansition

    Reverse Plan: "Requesting 5000, Direct to CSN, Direct to HEF"

    The Clearance: "Expect Radar Vectors to MRB after CSN, Expect 4000' ten minutes. Frequency 124.65, Squak 4640".

    Sunday, September 12, 2010

    Zero/Zero Takeoff

    When I line up on the runway, I check the Time, Lights, Transponder, Gyro (lined up with runway). What I have never done before is put the foggles on. Wow. Taking off with view limiting device is freaky. Its like the flying the airplane on the ground (a familiar concept to tail draggers). I focus on the directional gyro and the airspeed. That's it. Hope the runway is perfectly lined with the gyro and GO!

    It is good exercise, but not something I wish to put into practice. I would not want to take-off from an airport I could not find quickly or land on an approach in case of system malfunction.

    Preparing for the next instruments lesson

    Things I will remember to do:

        (1) Preflight: Review checklist with instructor and provide the instructor with a briefing include clear exchange of controls and I inform him that he is ATC today. Instructors like students that remain PIC, and I am the PIC.

        (2) Talking to ground: remember to say "VFR to Flucky" and "Information X".

        (3) When talking to simulated ground (aka instructor), read back verbatim the clearances. Be familiar with the transitions BEFORE meeting with the instructor to avoid getting stuck on transition names like NISAE then direct to Culpeper.

        (4) During taxi, verify all instruments.

        1. Airspeed 0

        2. Attitude level

        3. Altimeter at station

        4. Rate of Turn indicator green and level

        5. Gyro directional indicator lined up with taxi way and compass

        6. VSI level 0

        (5) On vacuum failure, need to use the compass. The compass stabilizes on east/west headings. Once passed, use the counting method. Use the turn coordinator for standard rate turns. Simply count seconds for every three degrees. 15 degree turn is five seconds. If the angle of bank can be determined, take the airspeed and drop a digit (divide by 10), add 5 to get the angle of bank (for 90 kts, 9+5 is 14 degree bank for standard rate turn.

        (6) Always keep resetting the time mentally. Consider times when reaching a hold, leaving a hold, leaving a fix, etc.

        Holds have been an interesting problem for me to solve. They're really simple. However, it takes some time to get one's head around it. When a approaching a hold, notice the inbound leg with respect to the current heading on the gyro. If the in bound leg's radial is on the top half of the directional gryo, then its a direct entry. If on the bottom LEFT, its a parallel approach. It on the bottom RIGHT, then use the tear drop, maintaining 30 degrees from the radial and bottom most tick on the gyro. The above assumes standard hold on the LEFT 'outbound'. ALWAYS no the side on which to hold!

    On the last flight, I got a bit flustered when first contacting tower once cleared for the frequency change from Potomac Approach. Here is what I should have said (hiding from reader what I did say): "Manassas Tower, N2229E on the ILS over DORGE for One Six Left". Tower's response, "Expect a clearnace to land at 3 miles". At one mile, no clearance, my inquiry: "Manassas Tower, N2229E over middle marker for 16 L" in, heads up!