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GAFB 98

Winter’s ways with dodgy days

It can pay dividends to spend a few minutes thinking about what might go wrong before getting airborne in these trickier times

Winter is coming!  Those who are aficionados of ‘Game of Thrones’ will recognise those words and the dread that they instilled within the storyline. But it’s time again for us also to think about the implications of a return to the cold, wet and often gloomy days of winter. For some, it’s a question of hanging up the flying kit and hibernating until next Spring, but for other brave souls there are enough crisp blue flying days to be had that justify that ever-hopeful check of the met forecast each day.

Whilst being weather-aware is always important, it’s even more so in the winter when there’s a temptation to get airborne when the weather is close to the limits and things can change rapidly and unexpectedly in flight. We keep banging on about Threat & Error Management (TEM) but it can pay real dividends to spend a few minutes thinking about what might go wrong with the weather before getting airborne in the winter months.

Whilst you will hopefully not fail to check the ‘forecast’ and ‘actual’ for your planned destination, have you selected a diversion that is in a more favourable area if the weather is at all dodgy when you arrive where you’re planning to go on that ‘A-to-B’ excursion? Even if you’re only going ‘A-to-A’, where would you go if the weather turned against you on recovery, and have you got a plan that keeps enough fuel in reserve to get there? This edition’s ‘I Learned About Human Factors From That’ (ILAHFFT) is a cautionary tale about pushing the weather that highlights some of the relevant decision-making.

When was the last time that you practised that 180° turn on instruments? Hopefully you won’t get caught out by pressing-on into bad weather but it happens! Why not seek out an instructor and gain some proper instruction on instrument flying before the bad weather really settles in and you may have to turn to those skills for real? Weather patterns and visibility levels encountered in this country can quickly catch out experienced and inexperienced pilots alike; you may technically be flying legally, but you need to be able to cope with those conditions confidently and safely, especially in reduced visibility situations approaching 1500m or when flying into that setting sun in hazy conditions.

Ice can also be a problem, not just airframe or carburettor icing but also on the runway and apron surfaces. Unexpected black ice or slippery airfield markings can suddenly take the edge off your day when you find out you can’t stop the aircraft so judicious use of power is a must, and always with the anticipation in mind that you may take longer to stop than you thought. Prior to powering up to start taxying, what is the surface like ahead, and can you turn or stop in good time if it goes wrong? Why not walk the ground ahead of the aircraft first before you get in and start up so that you can be confident that there are no icy or slippery areas as you start to taxy?

I remember well taxying one of HMG’s finest pointy fast-jet aircraft in Canada once when we hit ice at a 90° turn in the taxiway and ended up doing an uncontrolled 180° pirouette – sadly, I didn’t have enough brain-power left to work out which thrust reverser to use to stop the spin before we came off the ice and nonchalantly carried on taxying. Perhaps I should have tempered that first-tourist eagerness to get airborne and slowed down a bit as we approached that turn irrespective of having been assured that the airfield surfaces were all ‘cleared and de-iced’ before we got into the aircraft.

Whilst speaking of stopping (or not), ice on the runway may not necessarily increase your take-off distance but consider what will happen if there is a significant crosswind or you need to reject the take-off for some reason – how effective will directional control or the brakes be? Furthermore, it may well be possible to take off from a contaminated surface, but will it be safe to land again? On wet and muddy grass, the brakes will largely be ineffective. Similarly, on icy surfaces the use of brakes may cause considerable control difficulties (as I can testify!). CAA Safety Sense Leaflet No7 recommends additional safety factors for take-off and landing distances for other than dry surface conditions.

The bottom-line? Don’t push the weather, especially in winter, and have a Plan B for when things start to deteriorate. That way you hopefully won’t have to fall back on your instrument flying skills – but be ready and practised in at least the 180° turn on instruments just in case things go quickly and unexpectedly pear-shaped. Whilst on the topic of winter operations, CAA Safety Sense Leaflet No3 ‘Winter Flying’ contains many good gems that are worth reviewing before the hard weather arrives – why not take the time to sit by the fire in the clubhouse with a hot cup of cocoa and have a read so that you’re ready for when the weather doesn’t go quite the way you expected?

CHIRP provides a vital safety net as another route to promote change when the normal channels of reporting aren’t delivering results, you don’t feel able to report through formal Occurrence Reporting systems, and for collecting reports with safety concerns that did not meet the threshold for normal reporting and would otherwise have gone unwritten. We rely on you to report Human Factors aviation-related safety concerns to us so that we can both help in their resolution and highlight relevant issues to others.

Reporting is easy by using either our website portal or our App (scan the appropriate QR code shown or search for ‘CHIRP Aviation’ – avoiding the birdsong apps that come up!). In our reporting portal you’ll be presented with a series of fields to complete, of which you fill in as much as you feel is relevant – not every field is mandatory, but the more information you can give us the better. Although you’ll need to enter your email address to get access to the portal, none of your details are shared outside CHIRP, and we have our own independent secure database and IT systems to ensure confidentiality.

Stay safe!

Steve Forward, Director Aviation

  • GA1348

    –

    Change of Circuit Direction to Suit Straight-in Landing Business Jet
    Change of Circuit Direction to Suit Straight-in Landing Business Jet

    Initial Report

    Having got my newly minted PPL in Autumn 2019, I (and everyone else) had my plans and experience-building disrupted by COVID. I was only able to get back in the cockpit in late summer 2020, at a new and more local aerodrome to that where I did my PPL.

    I was aware of skills fade, the new airfield procedures & local area (and psychological doubting Gremlins that had crept in as a newbie) combining, so I undertook revision training. I found the new Aerodrome a good fit and felt I would settle well, with better procedures, clearer guidance and online aircraft/aerodrome specific documentation on a dedicated portal. 5 flights and 4 hours later, I was signed off to fly solo and hire aircraft. The same day as sign off, I went up for two more circuits to cement thinking of myself as a competent pilot (for my experience) to fly safely.

    Two weeks later, I returned, wanting to consolidate confidence and minimise future skills fade. I could only go after work so I planned only a few more circuits before sunset. The A/G radio was due to cease operating at 5pm so I had planned and confirmed the procedures to make blind calls on frequency, as I knew I would not be up before 5pm. Wind was low. Just a few quiet circuits, I thought. My take off time was 17:45. It turned out the A/G radio was still operating and so I flew as normal with A/G. I completed 2 circuits, building my confidence. In part of my circuit, the radio was readable but not good, but I was able to understand the calls.

    On the third circuit, I was downwind to land when a call from a small commercial aircraft requested a straight in landing on the same runway but from the opposite direction. The situation quickly became stressful for me. Imperfect radio and stress combined to hinder me but it became clear that the other aircraft was planning to land in the opposite direction to me on the same runway. My immediate thought was not to land but what exactly to do next?

    I don’t think this was covered in my training. I knew I had taken off with full fuel so didn’t ‘need’ to land right now. I called to say I was already established in the circuit (N.B. I had been for 20-25min) to land in the opposite direction to the other aircraft. Poor radio again, but I think I was being told to change the circuit pattern. Reasserting in my mind that I am responsible for myself and approaching base turn, I knew at the very least I couldn’t continue on. I wasn’t sure how far out the other aircraft was but two more turns and we could be nose to nose before I knew it.

    Calling before to assist all, I did a 180 degree turn away from the runway to begin another downwind in the other direction, offset from my previous track. Maybe I should have just left the circuit and orbited until I heard the other aircraft was clear. But my unfamiliarity with the area and stress level made me sure I wanted to stay “safe” in the circuit. I think I heard the other aircraft call a 4-mile final. This is a situation I had at least experienced before and the radio was better. I called to extend downwind until I had visual. I did and saw the other aircraft. I regained my confidence a little and called that I had visual and would position behind.

    Waiting for the aircraft to pass a good way, I turned base and went through the normal landing checks. The other aircraft seemed to have some confusion on which taxiway to take and was stationary on the runway, to a little exasperation of A/G to get them to clear. Having got myself back to a manageable situation, while on final I watched the aircraft with A/G stress rising and still trying to instruct them. Just above decision altitude, I decided and called to go around. There was some doubt, and I had had enough excitement for one day. A/G apologised. I landed safely on the next circuit.

    To an experienced pilot, this might have been an annoyance and some heated exchanges later. Even writing it, it doesn’t seem like that big of a deal. But the realisation of being out of your comfort zone without an immediately obvious path to safety was shocking. What are the ideal reactions for next time!

    Dirty Dozen factors involved: Stress and pressure – it was a highly novel situation to me; Communication – difficult so could not coordinate a response as effectively; Awareness – I seemed to have been forgotten about. The other a/c didn’t seem to be aware of me.

    CHIRP Comment

    CHIRP Comments: To an inexperienced pilot, this is one of those out-of-the-ordinary situations that can suddenly throw everything into confusion. The first thing to say is that within the SERA.3225(b) regulation, aircraft in the vicinity of an aerodrome shall “…conform with or avoid the pattern of traffic formed by other aircraft in operation” so it was for the business jet pilot to conform with the reporter’s circuit pattern or make sure that they avoided the reporter’s aircraft, not the other way around.

    That being said, it seems that the A/G operator had intervened and probably requested that the reporter change circuit direction to fit in with the business jet, which they did – at that point, it might have been worth asking the A/G operator to repeat their transmission just to confirm what they said if there’s any doubt in your mind. Remember that an A/G operator cannot instruct you to change circuit direction and, under an AGCS, pilots should not ‘request’ courses of action because an A/G operator is not empowered to grant such requests.  Instead, pilots should simply state their intentions so that others are aware and can integrate as appropriate.

    Having re-orientated themselves to the opposite circuit direction, the question then becomes ‘who has priority?’  Straight-in approaches are notoriously difficult to sequence with due to differing aircraft speeds and the sometimes unreliable range calls from straight-in pilots. But the over-riding requirement is covered in SERA.3210(c)(4)(i) which states that the higher aircraft shall give way as below:

    (4) Landing. An aircraft in flight, or operating on the ground or water, shall give way to aircraft landing or in the final stages of an approach to land.

    (i)  When two or more heavier-than-air aircraft are approaching an aerodrome or an operating site for the purpose of landing, aircraft at the higher level shall give way to aircraft at the lower level, but the latter shall not take advantage of this rule to cut in front of another which is in the final stages of an approach to land, or to overtake that aircraft. Nevertheless, power-driven heavier-than-air aircraft shall give way to sailplanes.

    So the bottom-line is that once they had changed circuit direction to match the straight-in business jet, the reporter did the right thing in going around when they found that the runway was still occupied as they approached – you can go around at any point in the circuit, even when downwind if you’re not sure what is going on or where the other aircraft is – just maintain your height and follow the circuit ground track (but fly deadside if possible rather than down the runway in case the other aircraft goes around and climbs away) to position yourself at the start of another downwind leg if necessary.

    Although, as we said earlier, it was for the business jet to conform to the pattern of traffic formed by the reporter and arrange their approach accordingly, for expediency it may be simpler to make way for such higher-speed straight-in traffic in order to avoid greater confusion if the business jet then had to go around itself and try to enter a visual circuit because it could not integrate from the straight-in approach. In making way, perhaps a better initial course of action when hearing the business jet call for the opposite runway might have simply been to either depart the circuit or go into the overhead at 2000ft and wait for the business jet to land before then re-joining the circuit.

    Finally, we commend the reporter for making their intentions clear on the radio for others to hear; even if they were the only other aircraft in the circuit it would have reassured the business jet pilot and A/G operator that the reporter was aware of and (eventually) visual with the other aircraft.

    Key Issues relating to this report

    Dirty Dozen Human Factors

    The following ‘Dirty Dozen’ Human Factors elements were a key part of the CHIRP discussions about this report and are intended to provide food for thought when considering aspects that might be pertinent in similar circumstances.

    • Stress –a situation not encountered before
    • Pressure – inexperience and uncertainty about what to do
    • Communication – if uncertain, ask others to repeat their transmission or clarify their intentions
    • Complacency – the business jet pilot seemed to assume that they had priority
    stress, pressure, poor_communication, complacency

  • GA1349

    –

    Radio Issue
    Radio Issue

    Initial Report

    Flying fairly late in the day with a first-time GA passenger as a favour to a relative, sunny with some haze, airport fairly quiet. Called for start and airfield information, no reply from the A/G service in the tower. Looked up at the windows, couldn’t see anyone in there, which wasn’t that unusual, nor was the lack of reply, so I didn’t think any more about it.

    Started, taxied out, completed pre-flight checks, called ‘ready for departure’, still no reply.  Again, not unheard of to have nobody in the air that late in the day and nobody replying from the tower, so I made a blind call that I was entering and backtracking [active runway]. Checked both directions of the active runway before crossing the double yellow line and entering the live side of the airport, entered the runway…and about halfway down the backtrack an aircraft on final appeared out of the haze.

    It immediately dawned on me that I had a radio failure, so I got as far over to one side of the runway as I could just in case the approaching aircraft hadn’t seen me, waited for it to go around, then performed a 180 and got back off the runway.

    Taxiing back in, there was someone halfway down the tower steps waving a handheld at me – my suspicions seemed correct. I made my apologies to all concerned, then taxied back to the hangar to see if I could discover the problem. I was very surprised, as the radio had been working perfectly a few days before when I had been talking to the local international airport and also someone on a handheld at a grass strip. I checked aerial connection, swapped headsets, swapped which pair of headset plugs I was connected to – all seemed fine.

    Then I noticed that where the frequency on the radio should have been showing a zero, it was showing an eight. I had returned to [Airport] out of hours when I had flown a few days before, and I must have inadvertently selected this incorrect frequency when switching back from the other services, but as it was out of hours there was nobody manning the tower A/G radio, so the lack of reply on return to [Airport] did not alert me to the problem. The difference between the 8 character on my radio and the Ø was a minor difference in the direction of the line in the middle of the character (horizontal on the 8, slightly sloping on the continental Ø it uses).  That small difference was pretty much invisible to me in bright sunlight, especially with the aircraft jiggling around during taxi. I selected the correct frequency, and everything worked perfectly.

    What more could I have done: check small displays such as radio frequencies in the shade of the hangar, with the aircraft stationary. I could see the error clearly enough when I did that, and would have avoided the problem completely had I done so before starting and taxiing. The other thing which occurs to me is confirmation bias. I believed the radio to be working and on the correct frequency because I thought that was the case on my previous flight…hence I interpreted all the subsequent information in the light of what I already ‘knew’. A more sceptical attitude would also have helped to avoid the error. But, ultimately, a quick glance at a small digital display in unfavourable lighting was the root cause.

    Dirty Dozen factors involved: fatigue, time pressure, distraction, but mostly complacency – the radio was working perfectly very recently, so radio failure wasn’t something I even considered when receiving no reply to several calls. Question assumptions!

    CHIRP Comment

    It’s really difficult to recognise a radio ‘failure’ on an aerodrome when it’s not unusual for there to be no other transmissions and it appears that no other aircraft are operating that might otherwise be heard on the radio. It’s easy to be wise after the event and offer advice about double-checking frequencies etc but what we need to think of is practical advice on how we might detect such situations. Before you walk to the aircraft, a confirmatory check with the A/G operator that they were operating would at least ring some alarm bells if you then can’t get hold of them before taxying. Also, with radio displays like these where an ‘8’ and ‘Ø’ might not be obviously different, it’s a good habit to select a digit one click before or after to confirm that this digit is what you expect (i.e. one click back from ‘Ø’ to get ‘9’ rather than ‘7’) before then returning one click to the desired digit.

    Key Issues relating to this report

    Dirty Dozen Human Factors

    The following ‘Dirty Dozen’ Human Factors elements were a key part of the CHIRP discussions about this report and are intended to provide food for thought when considering aspects that might be pertinent in similar circumstances.

    • Resources – poor radio display user interface
    • Pressure – desire to get the passenger airborne for their first flight
    • Communication – wrong frequency selected
    • Complacency – assumption that the radio was set to the correct frequency from the previous flight
    pressure, lack_of_resources, poor_communication, complacency

  • GA1352

    –

    NOTAM Understanding
    NOTAM Understanding

    Initial Report

    [Airport] have recently seen an increase in controlled airspace infringements. As a result of investigations and ongoing analysis, it has become apparent that this is at least in part due to an increase in pilots operating under the misapprehension that our airspace was closed (NOTAM’d deactivated). A common theme amongst a few of them is the use of ‘third-party software’ as an assist to flight briefing and navigation, and a failure to properly understand and assess the information displayed under the NOTAM tab.

    For example, during the month of June, [Airport]’s Class D CAS was de-activated daily between 2000-0530Z. When issuing a longer-term NOTAM covering set daily closure periods such as this, the NOTAM Office require us to issue the NOTAM from the 1st-30th, with a daily schedule for the closure periods, as opposed to a separate NOTAM for each day.

    We have approached the manufacturer of one such popular provider, who were most accommodating in their response. It seems that all information is readily available for the pilot. The problem seems to be the pilot’s interpretation of the information displayed. On investigation, it seems that an easy mistake for the pilot to make is to read the headline ‘Deactivated by NOTAM from X to Y’ and either misread, don’t understand, or fail to notice, the ‘Schedule’. They have the option to ‘touch for more details’, which opens the full NOTAM text in another box, but either this is not being done, or again the ‘schedule’ part is misunderstood.

    The purpose of this email is to ask, via the medium of CHIRP, that pilots using popular third-party systems as a navigation/flight briefing aid, are made aware of the need to fully interrogate NOTAM information as presented to them on a digital display, especially the ‘schedule’ part, and to be made aware of its purpose and meaning.

    Basically speaking, if ATC are operating, it’s best to assume that the CAS is also active. Always call in good time and ask, irrespective of what you believe the NOTAM says. If asked to stand-by, or no clearance is received, route around and avoid – operate under the assumption that CAS is active unless confirmed otherwise by ATC/ATIS. ATC are obliged to MOR every incursion, however minor. This includes those where mode ‘C’ indicates inside but the pilot reports outside.

    Please don’t rely on the summary page of nav-aid without question – it is no defence against the MOR!

    CHIRP Comment

    The report highlights the need for pilots to read all information within NOTAMs and not just take a cursory approach to acknowledging their presence from the title – this includes expanding all the NOTAM information to properly absorb its contents. That being said, some NOTAM titles are not helpful in themselves because they can give a misleading impression as to their content.

    For example, A NOTAM title such as ‘Notamville Airport CAS deactivation times 0900-1700’ intended to draw peoples’ attention to various times between 0900-1700 would probably be better titled as ‘Notamville Airport CAS deactivation schedule’ because this would then indicate that there was more information to be gleaned than simply reading the title and wrongly assuming the CAS was deactivated from 0900-1700.

    Although the report was a plea from a particular airfield, it has widespread relevance in reminding us all that there are often details within NOTAMs that may not be apparent at first glance: those compiling NOTAMs can help by thinking about how they make sure that readers are effectively pointed towards the information they need; and readers need to fully read NOTAMs to make sure that they access the complete details.

    Key Issues relating to this report

    Dirty Dozen Human Factors

    The following ‘Dirty Dozen’ Human Factors elements were a key part of the CHIRP discussions about this report and are intended to provide food for thought when considering aspects that might be pertinent in similar circumstances.

    • Resources – potential ambiguity in NOTAM titles
    • Knowledge – full NOTAM information not accessed
    • Complacency – assumption that NOTAMs do not need to be fully read
    lack_of_resources, lack_of_knowledge, complacency