Flying Hours Today 0:00, Total 45:25
P1 Flying Hours Today 0:00, Total 7:30
So the plan is for me to fly away for a couple of hours on a solo nav exercise and also spend some time in the air practising some of my skills such as PFL, steep level turns, stalling etc. etc.
Today I was to fly around the Vale of York. Setting off from Gamston flying to Linley Hill, up to Scarborough, spend some time doing general handling then locating Kirbymoorside.
From Kirbymoorside I would route south east to Brough and then return to Gamston. Of course this would be on top of the ferry flight from Sheffield to Gamston and back.
Arriving at the flying school the weather was touch and go, but I got on with the planning. As I was finalising the calculations on the very last line of the flight log the weather took a turn for the worse. The solo nav exercise would be off.
There were gusts of 30kts+ at Humberside and Teesside with the winds aloft at 185/40kts.
Plan B was to go up into the clouds and do some radio navigation, but even as we discussed this the weather worsened and it looked like the day would be written off. I took the opportunity to do some ground school revision.
Firstly we touched on drift angles and en-route diversions. It is good practice to sketch on the navigation chart the wind vector and strength so that you always have the right data to hand. Additionally I need to get into the habit of writing down the maximum drift angle for reference during a diversion.
To mentally calculate the drift angle simply divide 60 by your airspeed and multiply by the wind speed. For example, TAS is 100kts, wind speed is 40kts, maximum drift angle (in degrees) is (60/100) x 40 = 24.
In other words, a ratio of windspeed in kts and the airspeed in miles per minute. If TAS is 100kts this indicates 1.66nm/min, wind is 40kts, the ratio is therefore 40 / 1.66 = 24. So maximum drift angle is 24 degrees.
Make a note of this on the chart.
We then took a point on the chart and a diversion. Supposing that overhead Kirbymoorside we had to divert to Leeds. My guestimate of the angle from Kirbymoorside to Leeds was 230 and around 35nm - using my thumb as the 10nm marker on the chart.
From this calculate the difference in heading and wind = 230 - 185 = 45. The wind aloft on this day was 185/40 as stated earlier. Note that the smallest angle of interception between two vectors is used. If the wind is 220 and the heading is 360 then the difference is actually 40 degrees as this is the smallest angle between the two vectors - draw the two vectors on top of each other. The small angle is the bottom left one. Remember - always apply max drift towards the wind.
In other words, a ratio of windspeed in kts and the airspeed in miles per minute. If TAS is 100kts this indicates 1.66nm/min, wind is 40kts, the ratio is therefore 40 / 1.66 = 24. So maximum drift angle is 24 degrees.
Make a note of this on the chart.
We then took a point on the chart and a diversion. Supposing that overhead Kirbymoorside we had to divert to Leeds. My guestimate of the angle from Kirbymoorside to Leeds was 230 and around 35nm - using my thumb as the 10nm marker on the chart.
From this calculate the difference in heading and wind = 230 - 185 = 45. The wind aloft on this day was 185/40 as stated earlier. Note that the smallest angle of interception between two vectors is used. If the wind is 220 and the heading is 360 then the difference is actually 40 degrees as this is the smallest angle between the two vectors - draw the two vectors on top of each other. The small angle is the bottom left one. Remember - always apply max drift towards the wind.
Now use the clock method to determine fractions of the difference to take into account. As with many thing navigational and timing the number 60 is involved.
Simply divide the difference, 45, by 60 to get 0.75, then multiply the maximum drift angle by this : 0.75 x 24 = 18 degrees. From this we know that we need to steer a course of 230 - 18 = 212 degrees (true), plus the magnetic variation of +3 = 215 degrees (magnetic).
Our headwind calculation is similar and just as simple once you get your head around it. Once again, use the difference angle of 45 degrees but this time after dividing by 60 subtract the number from 1.
In our case 45/60 = 0.75, subtract from 1 = 0.25 i.e. a quarter of the wind component is our headwind = 40 x 0.25 = 10kts. If our TAS is 100kts then our ground speed is 90kts, so to travel the 35nm to Leeds will take 35/90 = 26 mins approximately.
So our rough check is: Heading 215M, at 100kts TAS, 90kts G/S, distance 35nm, time 26 mins.
Calculating this accurately on the chart and with the whiz wheel computer gives the following: Heading 214M, at 100kts TAS, 66kts G/S, distance 35nm, time 31.5 mins Close, but there is still some thinking around the calculation for ground speed.
As always, make a quick mental check that the figures are correct. If tracking, for example, 090 and the wind is from the south then you KNOW that you will have to fly a heading greater than 090 to ensure you not blown further north. Similarly if you are flying due south into a southerly headwind you will know that your ground speed will be less than your airspeed.
After a short pause for coffee we moved on to radio navigation. Another area where my understanding has become somewhat rusty but just need a short refresher. So we reviewed NDB, ADF, DME, VOR, RBI, RMI and the TITS mnemonic: Tune, Identify, Test and Select - mostly appropriate to the ADF for the Test part.
Simply divide the difference, 45, by 60 to get 0.75, then multiply the maximum drift angle by this : 0.75 x 24 = 18 degrees. From this we know that we need to steer a course of 230 - 18 = 212 degrees (true), plus the magnetic variation of +3 = 215 degrees (magnetic).
Our headwind calculation is similar and just as simple once you get your head around it. Once again, use the difference angle of 45 degrees but this time after dividing by 60 subtract the number from 1.
In our case 45/60 = 0.75, subtract from 1 = 0.25 i.e. a quarter of the wind component is our headwind = 40 x 0.25 = 10kts. If our TAS is 100kts then our ground speed is 90kts, so to travel the 35nm to Leeds will take 35/90 = 26 mins approximately.
So our rough check is: Heading 215M, at 100kts TAS, 90kts G/S, distance 35nm, time 26 mins.
Calculating this accurately on the chart and with the whiz wheel computer gives the following: Heading 214M, at 100kts TAS, 66kts G/S, distance 35nm, time 31.5 mins Close, but there is still some thinking around the calculation for ground speed.
As always, make a quick mental check that the figures are correct. If tracking, for example, 090 and the wind is from the south then you KNOW that you will have to fly a heading greater than 090 to ensure you not blown further north. Similarly if you are flying due south into a southerly headwind you will know that your ground speed will be less than your airspeed.
After a short pause for coffee we moved on to radio navigation. Another area where my understanding has become somewhat rusty but just need a short refresher. So we reviewed NDB, ADF, DME, VOR, RBI, RMI and the TITS mnemonic: Tune, Identify, Test and Select - mostly appropriate to the ADF for the Test part.
Being grounded was a good opportunity to go out to the aircraft and sit on the ground while going through tuning and identifying stations. For the first time I was listening to and decoding morse code. A much simpler exercise than I expected, especially when you know what to listen for and are simply confirming that the station is tuned. I'm by no means a morse code transcriber yet.
All this radio work was a useful refresher and a prompt for me to re-read the radio nav sections of Trevor Thom's book 3: Air Navigation.
We then moved on to the practicalities of the skills test. I requested the centre of gravity envelope sheet and the weight and moment data for the flying school aircraft.
It was only the second time I've seen the insides of a Pilots Operating Handbook. A useful opportunity to photocopy some of the relevant pages in order to review and get ready for the up coming skills test.
Finally it was time to review my log book and plan a final refresher lesson to take before or after my solo activity. I'm still about 0.2 hours - 12 minutes - down on my Stalls and Spin Awareness / Avoidance training so I'd want to cover a couple of turning stalls in various flap configurations.
Moving on to low level flying with regards to precautionary landing planning. Another practiced forced landing or two, some steep level turns then onto the VOR/NDB tuning and tracking. Following that I should be ready to go. Next weekend, if the weather is OK, I should have everything covered: a 1.5 hour refresher lesson booked, 2.5 hours of solo, then a skills test at noon. Fingers crossed!
All this radio work was a useful refresher and a prompt for me to re-read the radio nav sections of Trevor Thom's book 3: Air Navigation.
We then moved on to the practicalities of the skills test. I requested the centre of gravity envelope sheet and the weight and moment data for the flying school aircraft.
It was only the second time I've seen the insides of a Pilots Operating Handbook. A useful opportunity to photocopy some of the relevant pages in order to review and get ready for the up coming skills test.
Finally it was time to review my log book and plan a final refresher lesson to take before or after my solo activity. I'm still about 0.2 hours - 12 minutes - down on my Stalls and Spin Awareness / Avoidance training so I'd want to cover a couple of turning stalls in various flap configurations.
Moving on to low level flying with regards to precautionary landing planning. Another practiced forced landing or two, some steep level turns then onto the VOR/NDB tuning and tracking. Following that I should be ready to go. Next weekend, if the weather is OK, I should have everything covered: a 1.5 hour refresher lesson booked, 2.5 hours of solo, then a skills test at noon. Fingers crossed!
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