Tag: Wind

Posted on

A Cold Front!

Today my flying lesson was moved forward by 1 hour as the British weather forecast showed a cold front moving through around the time my lesson would be ending; it was Katie that had spotted this and the foresight to move it.

When I arrived I duly burped the aeroplane and pre-flight checked our C42 over, I could not get it out of the hanger as the wing would not clear Mick’s C42 if I tried. Not wanting to take any chances I went into the club house and asked Mick for his assistance and he happily obliged taking his aeroplane out of the hanger as he would be flying a little latter. I don’t like moving any aeroplane even the one I have shares in on my own, I believe it to be safer to have two people to do it one watching each side. This way the risk of causing “Hanger Rash” is reduced! For those that have not heard the term before, hanger rash is when one aeroplane bumps another and causes damage however slight. We have recently been the victims of hanger rash and although it only caused light damage to the aileron covering, it could had caused damage to the rods inside; this is why whenever you witness or cause hanger rash it is very important to report it, so the owner of the other aeroplane can check it out before flight. However there is a tendency to cover it up or not report it probably due to the fear of the costs of fixing the damage; however the real cost could be so much higher if not reported! Maybe the BMMA or someone could do a piece on it!

Anyway Katie and I were off and decided to do a flapless take off due to the wind, it was a good job too as it would have been very easy to over speed the aeroplane’s VFE  in these conditions.

Once again as we cleared the runway Katie declared an engine failure and I selected a field and we would have been down OK, these I don’t seems to have too many issues with.

We flow west towards the approaching front thus ensuring we could get back if it moved in on us. We made a few PFLs and I got in to some and was sort on others and even too high on a couple. The gusting strong wind made it difficult to judge. My selections of field although fine from on high often had power cabled crossing them as we got closer, making me reselect an alternative field. A tip from Katie here is to check if they have straight plough lines or if they have a “bump” in them if they do it is probably where they have gone around an electricity pole!

As the wind was too high for the parachutists we overflew Chatteris airfield and tried a couple PFLs there, again I was too short and then to high on my last attempt I got it just about right, however I thought I was going short an got my self-transfixed on the runway threshold causing me to round out a bit high resulting in a bit of a bump as we landed!  another thing in today’s lesson I had not come across before, is lowering the nose slightly in a strong wind will help stretch the glide a little, here we are only talking 5 kts or so and only a marginal extension in ground coverage, but every few feet could count in a real engine failure!

At least today I remembered to clean the aeroplane up on the taxi back, strobe off, transponder off and flaps up.

Another good thing today, the aeroplane was not to muddy so it was quick to clean, which was good as just after putting her away in the hanger the rain started, good timing!

Parked at Fenland
Posted on

A roller coaster of a ride!

It had been 4 weeks since I last flew and I wondered how much I could forget in such a short space of time, well the answer seems to be quite a bit! First off was the order of the checklist, it took a little prompting from Mike, but it was in there somewhere and soon came back!

During the 4 weeks the C42 has had its BRS (Ballistic Recovery System) removed and sent away to have the parachute repacked, to be able to fly it we had to have a new weight and balance done as the allowed flying weight drops from 472.5Kg to 450Kg without the chute in a microlight. We also had an oil thermostat fitted so it will warm up quicker and hold its temperature better, hopefully it will help prolong engine life too.

The aeroplane had not been flow today so was cold, however with the oil thermostat fitted it warmed up very quickly and I was able to do the power check almost by the time I got to it on the check list!

The weather was looking ok and within limits however the wind was blowing directly down runway 29; I have never flown from or landed on 29, it’s a lot shorter and narrower than our other runways and for good measure there are some cables on the approach too!

Runway 29 Chatteris

Take off was no problem and with the wind we gained height very quickly, we flew out to the west and over March and then turned towards Whittlesey while practicing trimming for 70, 80 and 60 knots, I struggled with this as I knew that for 70 the trim should be neutral and the power set to 4,200 rpm, however this was not working and it took me a while to figure out it was down to the balance of the aeroplane without the chute had changes and therefore I needed some extra trim. After some practice and some initial faffing around this was ok, but needs to be polished in a future solo. Next came unusual and dangerous attitudes, Mike took the controls with me lightly holding the stick and first put the aeroplane in a steep ascent and then said “you have control recover”, the recovery is easy enough, nose down and full power together until the nose is level with the horizon. Next Mike put it into a spiral dive, again this in my mind was OK power off, level the wings ease back on the stick and power on as the speed drops ones back in a climb, only problem I had was I closed the throttle, but not all the way so speed was building fast!

High rate turns was last on the agenda for today and I was pleased that I maintained altitude, however in the first turn I would have failed due to not performing the look out before the manoeuvre and my turn to the other direction I rolled out to soon, it should have been 360 and I rolled out at 270 degrees, in my defence I did spot another aircraft as we were through 180, but that was not an acceptable excuse!

Now it was time to return to the airfield and we were make slow progress at 3,000ft, Mike asked what I estimated the wind speed at and I guessed 60kn, he then said “well if its 60 up here will it be less or more at 1,500ft”, “less due to the friction of the earth” I said, Mike replied “good, so lets descend to 1,500ft and fly back at 80kn”. At 80 knots it was very bumpy, there was also a light rain storm just off to our left and as we came into land on 29 I was all over the show, it was like being in a roller coaster and I don’t like roller coasters! So we went around, the second attempt was more composed and the storm had moved away so the conditions were better too and we landed ok, it left me feeling quite shattered, but it’s all good experience!

Back on the ground I had with me a replacement bulb for our non-working MR16 halogen landing light. The replacement was a 9W LED and I fitted this after washing the aeroplane down, it’s a lot whiter light and brighter than the old one so long as it lasts, it’s a cheap, easy and good upgrade!

landing light lit landing Light fitted

Posted on

Navigation to Boston Airfield and Triangle of velocities

I arrived at Chatteris on what seemed a damp and grey day around an hour before my lesson to plan my flight to Boston as I was nearing the airfield I saw a C42 flying in the circuit and I was thinking to myself that the parachutists would not be jumping with such cloud cover, however as I turned into the track leading to the airfield I saw the twin Otter taking off closely followed by the main training C42. It often seems to have its own micro climate which allows for the microlight and the parachutists to go up while all-around the weather would not permit! When I left home it was layer cloud and raining but here it was scattered cloud and improving all the time.

In the clubhouse I made myself a cup of tea and set about planning out my route to Boston, possibly my last dual navigation to Boston, all was going well and I drew out the triangles of velocities on the whiteboard and then checked my results on Skydemon light http://www.skydemonlight.com/ which is a great piece of software and I hope to buy and evaluate it on either on an Android or iPad once I have my license (so Lookout for a future review of flying with this!) most of my calculation worked out ok and with little head or tail wind I didn’t notice my fundamental error! In fairness to me it has been a while since I did the Navigation exam!

Triangle of velocities

So how do you draw the triangle of velocities?

First Draw a vertical line to represent North with a diamond on the top to show it as a true north.

Next plot the course you want to fly, for this draw a straight line from A to B on a map and read off the heading using a protractor. For Chatteris to Boston we want a heading or Trk(T) of 349° so next we draw this line on.

Next go to the Met Office and get the spot wind for your altitude, Sunday this was 260/15 so we now need to draw this on.

 

The wind is drawn across the north line e.g. above I marked off 260° on the left of the north and drew through N and out far enough to be able to mark off the wind speed on the wind line. Add 3 arrows to show it’s the wind line. Take a ruler and mark the wind speed on the line from the north line, it doesn’t matter what scale you use mm, cm, your map ruler, whatever so long as all  the measurement use the same scale. I used mm on this drawing for the blog.

Next draw a line from 15mm along the wind line the length of the speed you will be flying and make the line intersect the Trk(T) line at that point . So below I have drawn from the 15mm mark a line that is 70mm (we fly at 70knts) where it joins the Trk(T) B – C below.

 So above we have:

A – B 260° line with point B marked at 15mm (from the Met office 260/15)

A – C our Track True from the map

B – C 15mm along the wind line (wind speed) 70mm long (our speed in knots) drawn to intersect our Track true at the 70mm point

If we now measure in mm A – C we get 67mm and this is by the magic of pythagoras theorem our Ground speed allowing for the wind 67 knots.

If we measure the angle of the line B – C   from north we get 336° our heading true.

And if we measure the angle D we get our drift angle 13°

Thank you Pythagoras!

So back to my flight planning well the fundamental error I made was I measured B – C as the ground speed even though I had drawn it 70 long for my airspeed!!!

The flight to Boston went ok, I got a bit off course, but spotting Fenland airfield I re aligned and was ok from there. I soon spotted Boston and just to the left was the airfield.

We landed OK (in fact for me it was quite a good landing!) and I got the teas in, while we were drinking our tea Mike was asked to do a check Flight which he agreed to do as no one was booked in after me. I stayed drinking tea and chatting to people. Sometime later we all watch Mike land and needless to say it was a perfect landing in every way.

Once Mike was done we set off back to Chatteris and the navigation all went to plan we joined on a long final for runway 24 and again the landing was not bad. I refuelled the plane and cleaned the prop and some of the birds muck off the wings, as while we were out Stuart had booked the aeroplane and it was not good to hand it over in the state it was in.

My next lesson in a couple of weeks’ time and weather allowing is going to be a solo to Boston and back!!!

 

 

 

Posted on

I’m leaving the circuit!

Another fun day to fly with variable and gusty wind and some light rain too!

Today was too windy to go solo and we were back on my least favourite runway used so far 21 (see previously posted the curse of the trees here ). Today’s lesson was mainly about leaving and rejoining the circuit, after taking off on 21 we climbed to 1,300ft, about 200ft below the cloud base and then turned towards Ely which we could see in the distance. I flew out to the drains and then turned through 180 degrees and came back towards Chatteris airfield, I knew it was ahead of me, but I could not see it at first. As we approached it Mike asked how I planned to rejoin the circuit for 21, my plan was to fly to the left and then come around and join on downwind, Mike had a better idea carry straight on and join on base leg, so long as I was down to circuit height before joining. I throttled back to 3,000 rpm and descended to 700ft, there was a lot of turbulence probably the most I have experienced in the microlight to date, I made the radio call to say we were joining base leg and proceeded to land. My approach was a little low so I added more power and came in well clear of the trees, in fact to high and a I rounded out to high also, so power on and around we went. We just flew the circuit this time and my landing was better, but not good so around we went again and this time it was acceptable. After climbing back up to 1,300ft we headed towards Ely once more and then back to the airfield, the weather was getting worse now with stronger gusts!  I spotted the airfield a little sooner this time and flew us back for a touch and go, the approach was quite good this time as was the round out, but then the aeroplane suddenly went up, thinking I must have ballooned I put the power on and went around, puzzled I asked Mike what I had done wrong, but for once it was not me, but a gust of wind that blew at an inopportune moment. We went back out towards Ely once again and as soon as I had turned back towards the airfield I spotted it, I think I must be getting used to seeing it, I flew us back for the last time and made probably my best landing of the day in what has to be the most challenging conditions I have flown in to date.

Shortly after I had refuelled  the aeroplane Simon arrived for his lesson, sporting his newly acquired headset, a nice pair of DC 10-13XL’s, he is just starting on circuits and made a couple of 50ft passes over the longer wider runway 19, however the weather continued to deteriorate and his lesson was cut short. Simon also has a share in the C42 so needed to refuel it after his lesson, he got his new Jerry can out and this is when we found out not all jerry cans are made equal, unfortunately his has a breather tube that restricts the opening to the point where we could not get the pipe from the pump in. Thus it’s worth checking this before buying a can, they should also have a UN number stamped on them. My Wavian Jerry can seems a good choice and Simon is now going to get the same.

Over flying Runway 19

Time for some tea and cake back in the club house!

Posted on

Grounded by the wind and how to take a strobe apart!

“When everything seems to be going against you, remember that the airplane takes off against the wind, not with it.” – Henry Ford

A nice quote from Henry Ford and quite apt after my previous blog post here, but alas when the wind blows hard microlight pilots can but sit and drink tea!

Another disappointing day today due to a different reason; Mike let us know that there would be no flying due to the strong and gusting wind, I really wanted to fly in the hope of putting last week’s trials well and truly into the past.

I decided to go to the club anyway for a cup of tea and a chat. On arrival I saw my instructor Mike outside cutting drainage channels into the concrete slab, I asked if there was anything I could do to help, but my timing was impeccable as Mike had just finished so I went into the clubhouse and made the tea. In the clubhouse were Katie and Pat, passing the time of day with their usual banter, but welcomed the offer of a cup of tea.

I went and took some pictures of some of the Microlights which I have uploaded to the photos page on this site here. Talking about the site there has been quite an upturn on the page hits over the last week with a new daily high of 105 and a number of days above 70 hits per day. This seems to be traffic coming from Twitter, a post on the Microlight forum asking for people to upload pictures and from Google with people searching for “air law notes”, I hope that it will continue, but time will tell.

Shortly after I had made the tea Mick and Julie arrived and they were soon followed by Alan who was carrying a food parcel of savouries and cake, always a welcome site! We all sat around passing the time of day and optimistically hoping the wind would die down so we could fly, however it did not happen.

Collision avoidance strobe

The collision avoidance strobe light on our aeroplane had been removed as it had stopped working a few weeks earlier, I asked if I could take it home to see if I could find what was wrong with it and I also like seeing how thinks work. It’s a Skyflash 2000 self-contained strobe only requiring 12V dc and no external driver unit; it is a sealed unit with no obvious way of taking it apart that could be successfully reversed if it could be repair.

Inside the strobe
Strobe

After careful examination and noting another’s attempt to open it I came to the conclusion the aluminium ring must be holding an upper and lower plastic moulding with the circuitry sandwiched between them, but try as I might the aluminium ring would not turn or move in any direction. As the unit was scrap anyway I decided to take a craft cutting disc to the band, as I carefully cut throughout the band it suddenly sprung open a little, working my way around the band I managed to separate it from the plastic body to reveal the construction I had assumed they used. It looks as if the band, upper and lower parts had a silicon type bonding agent keeping all of them together.

Now it was open it was obvious where the problem was, the storage capacitor had blown its top and leaked its electrolyte out for good measure.

Warning: Xenon strobes use high voltage for striking the flash tube it may only be 12V dc in, but its hundreds of volts across the tube.

 

I have ordered a new capacitor which cost a little over £5 and we will see if that is the only thing that is wrong with the flash unit once it arrives. If so the next challenge will be to find a tube with an internal diameter of 55mm and 27 mm in length to hold it all together!

To be continued…