HUMBERSIDE TAXI ACCIDENT (PART 1)

HUMBERSIDE TAXI ACCIDENT (PART 1)

Thank you to those who participated in this exercise which was to comment on the AAIB report and I apologise for the very long delay in publishing this. In Part 1 I will just deal with the errors and the areas overlooked in the report, as I see them. Disappointingly none of you who responded discovered any of these points.

The reason I took issue with the AIIB inspector, CAA and NATS is that there is supposed  be a big drive towards attempting to reduce the number of runway incursions and all of these agencies are supposed to be involved, pause for laughter! Runway incursions are caused by TAXIWAY & RUNWAY MOVEMENT ERRORS  (anyone remember Tenerife?).  When you read the following article just remember that 583 people lost their lives in March 1977 because of a TAXIWAY & RUNWAY MOVEMENT ERROR. It’s disappointing to note that several of the people I have contacted about this incident have shown an attitude not too dissimilar to the pilot responsible for the Tenerife disaster, Captain Jacob Van Zanten!

First a brief overview of the accident again

A Piper Saratoga was parked on the grass light aircraft parking area at Humberside Airport facing approximately 020 degrees. (we are not told exactly where the aircraft was parked)

It was the 61-year-old PPL holders first visit to Humberside, he was in current flying practice and had a total of 671 hours of which 300 were on type. He requested detailed taxi instructions and he was initially given instructions to join the grass taxiway towards Runway 08, but the controller subsequently decided there may be insufficient room for the aircraft to taxi safely along that route. The controller then amended his instructions, intending to route the aircraft to Runway 08 via hard taxiways. The pilot, it seems, became confused by the new instructions and inadvertently left the grass parking area perimeter edge prematurely, even though apparently signage was present to prevent this. After joining the fire vehicle access road and thinking it was part of the cleared routing, he subsequently collided with a roadside sign.

The accident was subject of an AAIB correspondence report,  which can be found here  AAIB REPORT

humberside-1

The black X in the above image shows the area where I think the accident occurred. Notice the lack of yellow centreline markings in this area as this is the fire service access road. The yellow centreline markings start from the concrete spur taxiway further along to the north and this is obviously where ATC expected the pilot to leave the grass and join the taxiway. The Airfield manager however says that this concrete spur isn’t in fact the normal way of leaving the grass parking area and only available to local based aircraft and that’s why the taxiway is undesignated! You see its a secret taxiway! Umh,sounds to me like making up rules as you go along. A taxiway with a yellow centreline marking is a taxiway at the end of the day and there is no mention of it not being available to visiting aircraft in the IAIP!

Google Earth picture of grass parking area and non designated taxiway

 

aerodrome chart

Looking at this aerodrome chart and the LIGHT AIRCRAFT PARKING AREA how would you get off the grass if you were trying to work this all out at the preflight stage? The only access is by what is shown on this chart as a vehicle access road in the north-west corner, the concrete spur, the very taxiway that ATC told the Saratoga to take. There are no access points shown around the perimeter of the complete parking area except the concrete spur taxiway. On the eastern side of the parking you will see a gap between the grass taxiway and the parking area, if you feel that you could taxi across that does that also mean you could carry on across the grass taxiway in a straight easterly line towards the runway as it’s the same light green colour- I don’t think so! (we will discuss this more in part two)

But help is at hand!

parkinganddocking

The Humberside parking and docking chart shows that you can in fact leave the light aircraft parking area directly onto the grass taxiway but notice where taxiway ECHO ends on this chart then look at the other chart. The aerodrome chart shows Taxiway Echo ending at the fire station apron, this chart shows it ending at the grass taxiway. Confusing isn’t it but when I pointed this out to the AAIB inspector he said there were not any problems with the Humberside charts? Hope he is a bit more thorough when he investigates a real accident!

Humberside Charts

Aerodrome Chart

Aerodrome Parking & Docking Chart

These links may not work so go to www.ais.org.uk/   and then to to the IAIP, then to AERODROME INDEX SPECIFIC and look at the Humberside charts.

We have been using this Humberside incident as a ground movement (Ex 5) training exercise for the last two years on both PPL & Flying Instructor training and I also threw it open to all 2000 of you via my internet blog for comment and again I apologise for the long delay in publishing this article.

Unfortunately no one who responded to my questions came up with the relevant answers to the errors that are contained within this report although everyone who responded agreed that the inspector’s report was difficult to understand in relation to where the aircraft was parked and how it got to the point of impact with the sign, with several commenting that a diagram would have been useful. Most of you mentioned some ambiguity and misunderstanding of the ATC instructions.

So here are the errors or points (as I see them).

1.TAXIWAY INCORRECT COLOUR ON NATS AIS CHART

The taxiway that the pilot was supposed to use was not (and is still not) shown in the correct ICAO colour (taxiways are sand coloured) on the aerodrome chart. This taxiway is still in use, as confirmed by ATC on the 8- 8-2016.

At the time of the inspector’s report the taxiway was shown in white, as it is now, this is, to my understanding, the colour for a vehicle roadway. This should have been picked up by the inspector and all of our respondents. When you inspect an aerodrome chart for taxi planning purposes it is essential that you can differentiate between dedicated vehicle routes and established aircraft taxiways. The way that you do this is by colour although several airfields that I am aware of have a confusing lack of sand colour on routes that are taxiways!  The taxiway from the eastern end of the hangar at Shobdon and some taxiways near the hangars at Gloucester for instance.

Another give away at a licensed or certified airfield, when you actually taxy, is that dedicated vehicle access routes DO NOT HAVE YELLOW CENTRELINES, if you are on what appears to be a taxiway and it has a white centreline, you are on a vehicle roadway! (this is rarely pointed out to PPL students!). It would have been appropriate and helpful if the inspector had mentioned this in the report too!

AIP GEN 2  GEN 2.3-2 (scroll down) shows the ICAO colours for taxiways, although note that NATS AIS do not follow these colours on the parking and docking charts!

GEN 2

 

  1. INCORRECT COLOUR OF GROUND MARKERS

The inspector’s report states;

The boundary between the parking area and the access road that the aircraft crossed was marked by seven low-level signboards with arrows pointing towards the access ramp. There were also triangular black-and-white striped ‘bad ground’ markers between the signs, warning pilots not to join the hard surface in that area.

Amazingly not picked by any pilot so far, or the AAIB inspector, was that the black and white striped bad ground markers are the WRONG COLOUR. The bad ground markers in this situation should be in fact orange and white. Black and White marker boards mark runway displaced thresholds and therefore should not be used for marking bad ground see  Chapter 6 page 7.3 – CAP 737 Visual Aids Handbook   This is basic PPL Aviation Law knowledge!

After several emails the Humberside airfield manager finally replied to me and said they had changed the colour of the markers to the correct colours after my email! He would not respond to any of my other comments but stated that the charts would eventually be changed but it could take some time!

  1. NO TAXIWAY DESIGNATOR

The dedicated concrete taxiway from the grass parking area, as shown on the Humberside aerodrome chart, does not have a taxiway designator letter which I find very unusual for a licensed airfield especially as CAP 168 states that all in use taxiways should have a letter designation. Although there does not seem to be any common policy for this and it is difficult to tell if some taxiways are for aircraft or vehicles. (parts of Shobdon and Gloucester for instance).

CAP 168 states

Taxiway location signs

7.41 Taxiway location signs should be used to identify individual taxiways.

7.42 All in-use taxiways should be designated by a letter of the alphabet

With no taxiway designator how do you look up a specific taxiway in the IAIP? In fact this taxiway is not mentioned in the IAIP entry for Humberside.

  1. Ambiguity

Designators also reduce ambiguity and confusion and it could be that the lack of a taxiway designator may have contributed in causing in some confusion for the pilot at Humberside. This was the RT question received by the pilot from ATC,

“CAN YOU SEE THE CONCRETE STRIP ON YOUR LEFT HAND SIDE?”

The pilot replied that he could, so the controller instructed the pilot to take it, and then Taxiway Delta.

If you look at the charts and especially the Google Earth presentation you can see that the concrete fire service access road (on the pilot’s left) looks like a continuous road to taxiway Delta but it in fact changes to a taxiway at the neck of the short spur but it remains concrete throughout and hence the possible confusion.

Google Earth- Humberside Airport

Ambiguity was most likely also compounded by the word ‘STRIP’ which as far as I am aware is not a word that is contained in CAP 413 in relation to taxi. The controller obviously meant the short piece of concrete taxiway that extended out from the access road and the beginning of the mystery taxiway proper (the spur) but the pilot obviously interpreted, ‘STRIP ON YOUR LEFT HAND SIDE’, as the concrete fire service access road even though there were ground markers to prevent premature taxi movement onto this road. Either of these metalled surfaces could be described as a strip! Again no one commented on the use of the non standard word, ‘STRIP’!

The report states; In the ATC tower, some 800 m away, the controller became aware that the aircraft was not exactly where he first thought, so warned the pilot “THE CONCRETE IS A BIT FURTHER ALONG THAN THAT” to which the pilot responded, “AH YES I CAN SEE IT NOW”.

Unfortunately ‘CONCRETE’ throws up another ambiguity because the complete vehicular road and mystery taxiway appear (Google Earth) to be of the same surface material, concrete!

Standard unambiguous phraseology is essential to prevent misunderstanding.

The pilot eventually replied “OK, I GUESS. IT’S A BIT NARROW BUT I’LL HAVE A GO”

The last call should have possibly alerted everyone that something was amiss and maybe also trigger some alarm bells with the pilot! The professional safe operation of an aircraft is not about ‘having a go’, it’s about managing the aircraft safely from one position to another using all the available information!

Why does this taxiway not have a specific taxiway designator letter? Note on the present aerodrome chart part of this mystery taxiway is obscured by the D2 holding point sign making preflight taxi planning even harder. This D2 sign should redrawn somewhere else.

For preflight planning (taxi) purposes, if I look at the aerodrome chart (using correct colours) the only way seemingly to get off the grass parking area at Humberside is via the southerly ECHO taxiway but if I look at the parking and docking chart I can only get off the grass parking area via the eastern edge of the parking area to the grass taxiway!

  1. Chart Anomalies

The Echo taxiway (south of the grass parking area) is shown as being a continuous aircraft taxiway all the way to the fire service access area on the aerodrome chart but if you look at the satellite picture on Google Earth the yellow lines seem to stop a long way before the fire service access area and are replaced by white lines. This was the case at the time if the accident report. So unless I am mistaken the aerodrome chart is in error here and the taxiway should not be shown entering the fire service access area.

However If you now look at the AIS aerodrome parking and docking chart this shows Taxiway Echo ENDING at the grass taxiway. In contrast the aerodrome chart shows it extending past the grass taxiway into the Fire Service Access area!

All the above points should have been dealt with by the AAIB inspector but when I wrote to him about this matter he was quite rude and obstructive and dismissed any suggestion of mistakes and refused to make any further comment. All of our respondents also agreed with me that the report did not make it usefully clear where the aircraft was parked and how it reached the board that it hit but again the inspector disagreed.

We are not told if the pilot completed pre flight planning which included looking at the appropriate AIS or equivalent chart of the parking area because the AAIB inspector apparently did not ask for any further information and merely relied upon the information as supplied to him by the various parties mentioned above. This I understand is standard procedure for an accident where there is no injury.

I cannot see the point of having AAIB inspectors looking at or getting involved with accidents like this as all they do is write up what the pilot wrote in his report and that’s hardly an investigation and this type of accident is already covered by the CAA Mandatory Occurrence Reporting Scheme (MOR). By giving no advice to prevent re occurrence, as the AAIB charter states that they are supposed to do, it might as well just be an MOR. As you can see from my article there is plenty of advice this inspector could have given if he had taken the time and trouble to do so.

We will look at how you can prevent such taxi errors in Humberside Part 2-coming shortly!

 

Would A Fighter Jet Shoot You Down?

Crossing an international FIR boundary without having filed a flight plan can produce some surprises such as a fighter jet formating alongside you and the pilot gesticulating to you and its unlikely to be a friendly wave!

1. You should immediately change to what frequency?

2. You do have on board a set of INTERCEPTION SIGNALS don’t you? (required by law to be carried on every flight, although the chance of being shot down in the circuit at Halfpenny Green are fairly remote even though the width of some pilots circuits probably do need a flight plan)

So what’s your best guess? if you failed to follow the fighter jet pilots instructions would he shoot you down?  Don’t think I would like to find out and in some countries I think it might be more, shoot first, ask questions later!

While I was instructing at Aberdeen one of the pilots next door in the Air Taxi company came back to Aberdeen one night from the continent without filing a flight plan and as he approached the coast two English Electric Lightning jets formated on him in cloud!  Unfortunately one of them actually collided with the Aztec, luckily this was more of a graze than a collision and both pilots landed safely afterwards!

lightening                   English Electric Lighting at Peterhead Airfield (Ex Teeside)- Photograph taken by Geoff Lokey

This pilot was not so lucky, note the phrase “was probably shot down”

Air Chief Who Stole Hercules Was Probably Shot Down!

A flight plan must be filed to cross the UK FIR boundary, so that does include going to Jersey and the Isle of Man

You are recommended to file a flight plan when flying more than 10nm from the coast over water

Ex 12 Performance Landing & Ex 13 Performance Take Off (Accident Examples)

Below are two different examples of incidents relating to performance take of and landing. The first one (pictured) is a take off incident on a grass runway at Breighton and the second a landing incident on a tarmac runway at Sturgate.

 

HDM ERM NEWS SOPHIE KITCHING 01-04-16 NOT MAIL COPYRIGHT The scene of an aeroplane crash. Pictures: Sean Stewart

The pilot reported that following the takeoff from the grass runway at Breighton, he intended to conduct a touch-and-go before flying to his home airfield at Kemble. The circuit was flown as normal and after touchdown full power was applied. The aircraft did not seem to accelerate, so the pilot closed the throttle and aborted the takeoff; however he was unable to stop and overan the end of the runway. The aircraft was severely damaged when it subsequently collided with a hedge. The pilot believes that the lack of acceleration might have been due to a possible combination of the soft grass surface and carburettor icing.

 

 

Piper PA-28-161 Cherokee Warrior II, G-BNXE

19 April 2016 at 1230 hrs-Location: Sturgate Airfield, Lincolnshire

Persons on Board: Crew – 1 Passengers – 2

Injuries: Crew – None Passengers – None

Nature of Damage: Damage to front and right wheel fairings and propeller and engine shock-loaded

Commander’s Licence: Light Aircraft Pilot’s Licence Commander’s Age: 73 years

Commander’s Flying Experience:1,290 hours (of which 850 were on type)

Last 90 days – 5 hours Last 28 days – 3 hours

Information Source: Aircraft Accident Report Form submitted by the pilot

The pilot was approaching to land on Runway 27 at Sturgate Airfield which had a dry asphalt surface and a length of 820 m. He described the wind as “light and variable”. He had made several ‘blind’ radio calls to which had received no response, during which he noted that the wind strength appeared to be about 4 kt.

On final approach, the pilot felt that he was slightly high due to noise abatement procedures over local houses and selected two stages of flap. On touchdown he felt that the wind had calmed completely, causing him to float further than he would have expected, with the result that the aircraft ran off the end of the runway and into an area of ploughed land.

Yet again another example of an AAIB report which does not contain any useful advice to prevent recurrence.

On reading the report it’s obvious that the pilot was uncomfortable and uneasy about this approach and landing. If he had translated that unease into a positive command decision and flown a go around, I wouldn’t be writing this. However the selection of flaps 2 instead of flaps full and the precedence given to a noise abatement procedure rather than the safety of the aircraft shows some flawed thinking and very likely, poor training. The first priority is the safe flightpath  of the aircraft, not a noise abatement procedure.

We are not told of the weight of the aircraft or the speeds flown (another  example of the inspectors lack of investigation, they just seem to accept what is written with no further communication) so it’s difficult to consider that but 820 metres landing distance is a respectable distance to achieve a successful landing in a PA28 so we must assume that the threshold speed and height was too high.

Unfortunately the present ‘Tiger Moth’ syllabus of PPL training seems to differentiate between a short field or performance landing and an ordinary landing to an extent that many pilots don’t seem to really know when to adopt a short field technique. Why not try my technique, fly every approach as a short field or performance landing and just make the brake application the only difference. Why fly overspeed at the threshold anyway, you’ve only got to get rid of that speed with the brakes or at worst with the downwind hedge!

So;

Decision making is about prioritising and flight path takes priority over noise abatement.

Have a stable height target (ours is 200 feet) If you are not stable at 200 feet-GO AROUND

Have a threshold target speed. If you’re outside that speed – GO AROUND!

If you find you are floating and are concerned about the remaining landing distance- GO AROUND!

If landing distance is a concern use flaps full but be stable by 200 feet

Ensure you can fly (and are in current practice) a short field approach using the speeds and technique as described in the flight manual.

Beware of bar room experts who say add 10 knots for your family, fly the published speeds.

Read the CAA safety sense leaflets http://publicapps.caa.co.uk/modalapplication.aspx?appid=11&mode=list&type=sercat&id=21 on

Contact the AAIB and ask then why they cannot publish some recommendations as I have done above. After all they state their aim is to investigate accidents and make safety recommendations to prevent recurrence!