Tuesday, 28 October 2008

PPL: Ex 18 Navex Debrief

This is a "debrief" with regards to the Navex flown today. It was a very good exercise and very well planned. What impressed me most was your progress in general and your R/T in particular. This "entry" is very much experimental, so I would expect some feedback - by whatever means! Today we were flying a Cessna 172 Skyhawk:

The planning was good. Weather and NOTAMS downloaded. Accurate track angles and distance measurements. Correct calculation of TAS (+06 deg C at 2000 PRESS ALT in the AIR SPEED window gives 102kts TAS opposite 100 KIAS). My old eyes don't help with that tiny AIR SPEED window!.
Correct application of the Wind Vectors to True Tracks which resulted in correct True Headings.
Correct application of VARiation (3-deg W) to obtain Magnetic Headings (HDG M). DEViation and therefore Compass Heading (HDG C) to be read from the Deviation Card on the instrument panel.
The Weight & Balance Form was filled out correctly. 116 litres of fuel confirmed in the tanks. Using the flight computer (wizz wheel - Ltr. opposite 116 gave 25.5 opposite IMP.GAL.) 25.5 IMP.GAL* = 183.6 lbs @ 7.2 lbs/Imp. Gal. (*Note: 25.5 IMP.GAL would equate to 30.6 U.S.GAL. - just look at the figure under the U.S.GAL mark on the computer! In Europe we have to get used to working with Lbs., Kilogrammes, Imp. Gals., U.S.Gals., Litres, Feet, Statute miles, Nautical miles, Kilometres, and Metres. An aircraft manufactured in the U.S.A will probably be quoting performance figures in Lbs. and U.S. Gallons, Feet and Inches, and, on older aircraft MPH in the POH/FM.)
The Weight & Balance Form (or Loadsheet) for our Cessna 172s uses the units Lbs. and IMP. GALs. (Note: Airliners in Europe are normally operated in Kgs. for both Aircraft Mass and Fuel Mass, but the fuel bowsers usually deliver fuel in Litres. Fuel energy is measured in mass. It is therefore important to ensure that enough volume is uplifted to equate to the mass required!)

Having calculated the Total Weight (2290 lbs.) the Short Field Performance (10 Flap) was calculated using ISA Temperature and Pressure Altitude of 200. Ground Roll = 240m. TODR = 410m. Both X 1.25 (+25%) for Wet Grass = 300m and 512m resp. TORA at EGBD = 453m. TODA 585m.

It was good to see that "Off Chocks" (or Brakes Off) time was recorded on the PLOG with a space left for "On Chocks" above. This makes it easy to subtract one from the other for "Total Chocks Time". Same for "Take-off" and "Landing Times".

Passenger Briefing, Start-Up, Taxy Checks and Power Checks all completed to a good standard. This was an unfamiliar aircraft with a different engine instrument layout. Nothing was missed. The technique of Think - Delay - Act worked well. There is never a case for rushing in an aircraft. A cool, deliberate, measured and considered approach to everything pays dividends. In fact it normally saves you time, and certainly can spare you embarrassment.

The take-off time was mentally noted. The take-off was smooth with aileron into wind and effective use of rudder to keep straight during the ground run. When elevator authority was felt through the control wheel, the nosewheel was lifted just clear of the grass. At 53KIAS the aircarft was rotated to the correct initial ATTitude for a Vx climb. Enough right rudder was applied to keep the aircraft balanced (ball in centre). You obviously understand the translation of the rudder function from ground to flight.

When the obstacles were cleared you adjusted the ATTitude by pitching down slightly in order to accelerate. Flaps 0 and attitude re-adjusted: Vy climb speed of 75KIAS. ATTITUDE - POWER - TRIM - excellent!

Using LOOKOUT - ATTITUDE - INSTRUMENTS and POWER - ATTITUDE - TRIM you climbed towards the first waypoint and called the aerodrome AGCS (Air Ground Communication Service - "Callsign" + "Radio") and advised that you were changing to "XXX Radar on xxx.xxx" your en route frequency. Your R/T is progressing very well. Obviously you are applying THINK - DELAY* - SPEAK to good effect too. (*DELAY only for a second or two.)

I would like you to work a little more on cockpit organisation. Here are some pointers:
One of the important points when flying is correct prioritisation. Flying is about prioritising correctly and effectively. Ask yourself, "What is important NOW?" The priority list has to be re-shuffled as required, and tasks or functions that have been pushed down the priority stack must be re-visited when conditions allow.
Obviously the priorities, as always, are AVIATE - NAVIGATE - COMMUNICATE, but within these tenets are sub-priorities. A major priority is LOOKOUT. In order to facilitate good lookout it is important not to spend much time looking in at stuff on your lap or kneeboard (in fact I recommend getting rid of the kneeboard), but to be well organised in the cockpit. Keep it simple. Organise all the information that you require in a simple & retrievable form. I recommend making up an A5 Handy Dandy Clearview Folder with all the information that you may need for the trip and tucked behind the seat. Simply use your chart folded to the standard 16 X 26 cm (or 7 X 10 inches). Clear & uncluttered thin black track lines drawn with 1/4, 1/2 and 3/4 distance marks on each leg. The only black on the ICAO 1:500,000 Aeronautical Chart is the printed names of towns and railway lines + grid lines of course. Tucked into a sleeve of the chart, or placed underneath the chart, would be the PLOG. The A4 size plog would be folded in half (A5 size) so as to fit neatly into the sleeve with the priority side UP. This is so that when the plog is slid out from under the chart the higher priority information is immediately visible. Of course all the information on your plog (your flight plan) is important, but I would suggest the side of the plog with MAG HDG, DIST, TIME and FUEL REQD are the immediately required values for each leg. Organise any notes, frequencies, radio aid information/idents etc. on this same side. Other priorities, of course, are accurate heading (HDG) and accurate time keeping (CHRONO).

Keep a green standard chart marker "lumocolor" pen in your shirt pocket for writing en route in a convenient, unimportant place on the chart. Green is a good colour because the only markings on an ICAO 1:500,000 Aeronautical Chart in green are forests and woods. Some pilots also use green for track lines. I like the clarity of black track lines and the contrast with green for "other" information, like Take-off Time, Squawk Codes, Frequencies, Revisions, etc. However, try to really listen and absorb information such as squawk codes, clearances and frequency changes so that you don't have to write them down! Mentally: Note - Repeat - Apply as you did today.

Avoid cluttering your chart with "drift" lines. From the index at the right of this page go to PPL Ex 18 (xiii): Navigation: (Off-Track Correction) to revise how to regain your track and make it to the waypoint. Please also re-visit PPL: Ex 18 (viii): Navigation: Heading & Chrono Discipline.

The final point is about the THROTTLE in the cruise. Set the cruise RPM (say, 2200RPM), tighten up the throttle friction and, in general, leave the throttle alone. Fly straight and level by LOOKOUT - ATTITUDE - INSTRUMENTS. KEEP the aircraft in TRIM and correct any (hopefully minor) ALTitude excursions with the control wheel (elevator). The speed excursions will thus be evened out.

Approach and Landing: Textbook!

Your Planning, Take-off, Climb, Situation Awareness, Lookout, R/T, and Overall Progress is very good. The main points are to do with being organised in the cockpit and leaving CRZ POWER constant. Again, well done.

1 comment:

skinardo said...

There are some excellent pointers in this debrief. I am at a similar stage of training and find that even with careful preparation and growing confidence there are moments when the tipping point between coping and task overload is reached. I am beginning to appreciate how vital it is to be able to prioritise and "aviate, navigate, communicate" is a really useful maxim. Also, making the most of the quieter phases of a flight to anticipate and mentally order tasks at the next waypoint, or conduct a FREDA check, can help spread the workload. I must say I'm envious of students who get this quality of debriefing as it maximises the impact of the flight training. The instructor I've been flying with,despite his "textbook" landings is a bit dull. The other day, whilst we were flying, I pointed out a Buddhist monastery and he made some remark that indicated to me that he wasn't really bothered.