The Weather Checklist for Pilots - Part 2

Having highlighted all the essential components of weather to look out for in Part-1 of this series, Here is my effort in the direction of coming up with a challenge/response type of checklist.

Since VFR/IFR are two options for flight, it’s the first item Pilots need to ascertain.

Challenge: VFR/IFR flight?

PilotFlying(PF) Response: VFR

PilotMonitoring(PM) Response: VFR

Visibility must next be checked out.

Challenge: Visibility greater than 5000m?

PF Response: 6000m

PM Response: 6000m

Wind direction and speed should be got hold of. Cross wind component must be calculated beforehand so that we can determine whether it’s within aircrafts permissible limits.

Challenge: Wind Speed and direction within permissible limits for flight?

PF Response: 280 Mag/7 Kts - permissible

PM Response: 280 Mag/7 Kts -permissible

Temperatures then should be found out. Cloudbase height calculated to check if it’s acceptable.

Challenge: Temparature and Dewpoint, cloudbase height acceptable limits for flight?

PF Response: 24 deg C temp/12 deg C dewpoint ; cloudbase - 4800ft - acceptable

PM Response: 24 deg C temp/12 deg C dewpoint; cloudbase - 4800ft - acceptable

Pressure then should be obtained.

Challenge: Pressure to be set in altimeter obtained for flight? Qfe/Qne/Qnh

PF Response: 1008 Qnh ; Flying altitudes

PM Response: 1008 Qnh ; Flying altitudes

Clouds then need to be identified. Presence of serious clouds like CB/TCU, Cloud layers should not add up more than half the sky

Challenge: Clouds checked and Clouds coverage more than half the sky?

PF Response: No CB/TCU, less than half the sky

PM Response: No CB/TCU, less than half the sky

TAF carefully accessed for the entire duration of flight with buffers if returning back to same Aerodrome else all aerodromes - departure, destination and alternate checked for potential problems.

Challenge: Weather acceptable for entire journey including destination and alternates?

PF Response: Departure, Destination and Alternate Weather acceptable for landing.

PM Response: Departure, Destination and Alternate Weather acceptable for landing.

Satellite images have been carefully gone over to check for any anticipated weathers approaching from the furthest point. Here, unlike high end commercial aircrafts which boast of weather radars, one must carefully go over them before hand to be mentally prepared. Pilots must exchange the same weather images.

Challenge: Satellite Weather image verified and risks manageable?

PF Response: Image:X,Y checked - manageable.

PM Response: Image:X,Y checked - manageable.

The above could be good checks, one could perform pre-flight and go ahead with flights. The same is presented below in table format.

Challenge	PF Response	PM Response
VFR/IFR flight?	VFR/IFR	VFR/IFR
Visibility greater than 5000m?	xxxx mts	xxxx mts
Wind Speed and direction within permissible limits for flight?	xxx Mag/y Kts - permissible	xxx Mag/y Kts - permissible
Temparature and Dewpoint, cloudbase height acceptable limits for flight?	xx deg C temp/yy deg C dewpoint ; cloudbase - zzzzft – acceptable	xx deg C temp/yy deg C dewpoint ; cloudbase - zzzzft - acceptable
Pressure to be set in altimeter obtained for flight? Qfe/Qne/Qnh	xxxx Qnh/Qfe/Qnh ; Flying altitudes/heights/FlightLevels	xxxx Qnh/Qfe/Qnh ; Flying altitudes/heights/FlightLevels
Clouds checked and Clouds coverage more than half the sky?	No CB/TCU, less than half the sky	No CB/TCU, less than half the sky
Weather acceptable for entire journey including destination and alternates?	Departure, Destination and Alternate Weather acceptable for landing.	Departure, Destination and Alternate Weather acceptable for landing.
Satellite Weather image verified and risks manageable?	Image:X,Y checked - manageable.	Image:X,Y checked - manageable.

Notes:

1. Pilot Monitoring responses in case of Solo flights could be an instructor or fellow pilot buddy.

2. Feel free to correct any inconsistencies/add more information to the above.

3. One of the feedback I received for Part 1 of this series blog was to include the sources of Weather I normally gather from. Below are my usual ones:

Mobile/Tablet apps:

·         Aviation Tools Free (aviatools.blogspot.com)

·         StationWX Lite (stationweather.com)

Both the above apps give METAR and TAF for a whole lot of locations.

·         Weather Underground(wunderground.com) - this app gives satellite images of weather.

During my flight training days, we used to collect ARFOR for cross country flights, obtained from:

·         olbs.amsschennai.gov.in - a met watch office portal of India Meteorology Department(imd.gov.in) for aviation. Also has METAR,TAF, Satellite images and a host of other weather related stuff.

The Weather Checklist for Pilots - Part 1

Weather - pilots best friend cum troubler in chief. All books on Piloting mention about checking the weather at both source and destination. If we look at many aircraft checklists too, it has a weather checked - item among a host of pre-flight checks. I was trying to demystify the above single item check on the checklist and thought about coming up with a detailed sub checklist for weather to be completed by all pilots. Let me elaborate my efforts in this direction:

1. Visibility:-  Whether you are in Visual Meteorology Conditions(VMC) or Instrument Meteorology Conditions(IMC), its essential to know the visibility because without it, taxying cannot be started. To know visibility, one must check METAR report or obtain it from ATIS. Future trends can be obtained from TAF. However, old school method of knowing visibility is to check for a known distant marker object from a predetermined position to get a fair idea. Having said that,  let me narrate an incident that I faced during my flight training days. We used to have a marker and it was clearly visible, but our Aerodrome METAR had a lower report(Controlled AD) and we used to go ballistic about it. However, during one of my pre-dusk arrival from long cross country flight during hazy weather day, we couldn’t clearly see the end of downwind marker(we used to have markers on ground in circuits) before joining the downwind. Upon landing, the fixed visibility marker was clearly visible. This was ample proof that old school ways, though serving the purpose, are not to be relied on 100% as they are indicative of straight line visibility whilst what is needed for Pilot is slant visibility and is accurately obtained from METAR/TAF/ATIS.

2. Winds:- Winds are essential component as they are the basis of flight. Wind speed and direction can be obtained by looking at the windsock at the runway(conventional) or from METAR/ATIS and TAF(future trends). It helps determine the runway orientation to use and also the drifts one can expect in flight.

3. Temperatures: Temperatures are a good indicator for engine performance and flight conditions. Temperature and dew point are obtained from METAR/ATIS. TAF does not include any temperatures. ARFOR could be used to determine enroute temperatures at higher flight levels. From temperature and dewpoint, we can deduce the cloud base height to help us determine safe cruising altitude to opt for. It also gives clues on icing conditions that one could encounter.

4. Pressure: Its essential measure to set in our aircrafts altimeter before start. Pressure can be obtained from METAR/ATIS. All heights/altitudes/FLs are dependent on the correct setting made by noting the appropriate pressure(Qfe/Qnh/Qne). Besides, it can also be an indicator of aircraft performance.

5. Clouds: The height and amount of clouds can be obtained to understand the climb profile and cruise altitude to opt for and also any deviations or infact NoGO/NoTakeOff conditions can be determined. During my training days, I used to wonder if the heights were as per name say AGL or altitudes or FL - in this regard I used to try to roughly measure the cloud heights while flying below it and tried to be oversmart or overdumb in the process. But in reality, the clouds are mathematical deductions based on angle subtended at the point of observation and instruments used(ceilograph) - hence are to be treated as heights(AGL).

6. Extra weather phenomenon: Weather is not constant and the predicted changes can be obtained mainly from TAF with indicators like FM/TEMPO/BECMG/INTER/PROB etc. These must be carefully assessed and Flight/NoFlight can be determined.

7. Weather Images: Satellite weather images of current and expected trend images should be checked. These can be obtained from your Local Weather Services Agency or could be obtained from viewing the images in Newspapers/News TV channels. These are indicative of strong weather conditions that are likely to be encountered.

After gathering above data, I have come up with formulating a checklist which follows a flow that could be followed similar to an airplane checklist coming up in part-2 of this blog series.

Notes:

1. All the above weather information represented is based on information I used to gather for my flights during my training days(SE & ME aircrafts).

2. Airline Pilots/other pilots could have more information at hand in the briefing documents received - I have no information regarding those - request readers to pitch in with their views to enhance the above effort to come up with the checklist or if already any such checklists exist, please do share if allowed to.

Flying ILS Approach: Glass cockpits Vs Steam Gauges

Being an Instrument rated pilot and having flown both 'round dials' or 'Steam gauges'(C172) and glass cockpit(DA42) aircrafts, I was analysing what are the differences between the two/which is better. But sitting idle at home whilst preparing for job interviews, I decided to take this seriously to help me, keep in touch with the subject. Going by my background of being a software developer in my recent past, I would have a leaning towards glass cockpit.

To be honest, I was not very accurate with my ILS flying on glass cockpits as I was with steam gauges. I decided to dig deep, to understand my fallacy and concluded that ILS representation of glass cockpits, DO NOT enhance the Pilots experience of flying vis-a-vis Steam Gauges. It’s a very strong conclusion to make considering my software background and only over 50 hours of instrument flying (Actual aircraft and simulators) up my sleeve. Let me elaborate my view and would be happy to be proved right or otherwise. I could also be blamed as ‘making an excuse’ for being a lousy pilot 😆.

First let me explain ILS for all: ILS or Instrument Landing System is ground based instrument aimed at facilitating an aircraft to precisely be guided to the runway, specifying the direction and height to be followed. Aircrafts have instruments to read the data offered by the ground based equipment and these instruments guide pilot to fly left/right (Localiser Indicator) and Up/Down (GlideSlope Indicator). The aircraft equipment in older aircrafts was by a single instrument (round dial - ILS) and in newer aircrafts by modern software User Interface (UI) representation.

First the software approach: During my software development days, I was not well versed with UI front end development - however, here I am commenting on experts UI! From a software development perspective, the current representation of having a localiser needle associated with direction indicator and GlideSlope indication associated with the altimeter tape makes great sense. Wow! It meets the functional requirements - Yay! Let’s Implement! - Really?

Though it makes great sense and looks perfect on FRD documents, I don’t think it does meet the end user - Pilot's requirement - in terms of change or added complexity to the pilot’s actions.

Now Pilots perspective: During final approach, 1st task would be aligning directionally as directed by localiser then latching onto glideslope and descending as per profile. While descending, the actions of pilot, which differ with respect to both steam gauges and glass cockpits, that I am unhappy about and hence this rant.

During the final stages of descent, the pilot must scan the crucial instruments of Localiser, glideslope, altimeter and ASI besides a lookout for horizon/runway, approaching the decision altitude. The workload on Pilot is immense at this stage - his bodily organs/parts like eyes, ears, hands, feet, nervous system and brain have to process and act with utmost precision. 

In glass cockpits, the scan of instruments, as shown in the picture below of Garmin G1000 cockpit display, follows the pattern of GlideSlope(scan gathers more information like height and ROD too – In Image below represented as 1) then localiser (scan gathers more information of direction – In Image below represented as 2) then Speedtape(In Image below represented as 3) and finally the horizon looking out for Runway(In Image below represented as 4 but is actually beyond the image). The eyes follow a quadrilateral scan pattern (In Image below – 1to2to3to4and1). Even a minimalistic scan would need a scan of GlideSlope then Localiser and the horizon - here the eyes follow a triangular scan pattern (In Image below – 1to2to4and1).

In Steam Gauges, The scan of instruments in C172 traditional cockpit, The glideslope and localizer(In Image below represented as 1) are covered in single instrument scan, then a straight line scan to left towards altimeter(In Image below represented as 2) and ASI(speedometer, In Image below represented as 3) followed by horizon scan(In Image below represented as 4). The eyes follow a triangular scan pattern (1to2to3to4and1) instead of a quadrilateral scan pattern, because the need to scan DGI, is avoided with localiser needle incorporated in the ILS instrument along with GlideSlope needle.

Even if theoretical experts argue that I may be following a wrong scan pattern, practising pilots on steam gauges even just follow a straight line scan (In Image above 1to4and1) of ILS instrument and the horizon which is bare minimum scan. More tolerance towards varying behaviors should be considered while designing any product. In reality though the pilot flying would be following the straight line pattern, the Pilot monitoring does scan all the other instruments and calls out the necessary information.

The scan pattern differences, in my opinion, add to the complexity of brain processing as well as a few extra micro seconds of time required to perform the actions on glass cockpits. Careful experts of Human factors Ergonomics practitioners might see the merit in my argument and request them to conduct studies around the same and publish data along with findings.

Feel free to comment.

Notes:

1. The scan of all important AI, is not mentioned as the attitude for descent is finalized when established on glideslope and aircraft is trimmed in that position.

2. G1000 Image obtained online from the link: http://krepelka.com/fsweb/learningcenter/navigation/usingtheg1000.htm - a good learning source. Unfortunately could not find - ‘contact me’ address on the page.

3. C172 Image obtained online from the link: https://flyawaysimulation.com/media/images6/images/Panel-And-FDE-For-Default-Cessna-172SP-fsx2.jpg . Flyawaysimulation is a great place for simulator software downloads.

4. Please excuse my poor Paint skills😞.

Disclaimer:

As it’s a personal opinion of interest to pilots interaction with systems and scope of learning involved, It should not be viewed in legal or commercial angles.