Jet Time B737 at Las Palmas on Feb 25th 2018, landed below required minimum fuel

Last Update: February 3, 2022 / 19:10:40 GMT/Zulu time

Bookmark this article
Incident Facts

Date of incident
Feb 25, 2018

Classification
Incident

Airline
Jet Time Finland

Flight number
JTG-427

Departure
Aalborg, Denmark

Destination
Tenerife South, Spain

Aircraft Registration
OY-JTY

Aircraft Type
Boeing 737-700

ICAO Type Designator
B737

A Jet Time Boeing 737-700, registration OY-JTY performing flight JTG-427 from Aalborg (Denmark) to Tenerife South,CI (Spain) with 148 passengers and 5 crew, was descending towards Tenerife South when the crew entered a hold at FL240 due to traffic congestion as result of a storm battering the Canary Islands. The weather conditions worsened and fell below minima for the approach prompting the crew to explore options to divert with ATC. After several attempts the crew was diverted to Las Palmas on Gran Canaria Island. When approaching Las Palmas ATC advised the aircraft would need to hold for 25 minutes due to traffic congestion. The crew therefore declared Mayday as landing with the required minimum fuel was no longer assured. The aircraft was thus vectored for the approach and landed without further incident but below the required minimum fuel reserve.

Spain's CIAIAC the aircraft landed with an amount of fuel that was below the required minimum. An investigation has been opened.

The aircraft refueled in Las Palmas, departed about 100 minutes after landing and reached Tenerife South with a delay of about 3 hours.

On Mar 8th 2019 the CIAIAC advised in a preliminary information, that the investigation has been completed and the final report will soon be published.

On Feb 3rd 2022 the CIAIAC released their final report concluding the probable cause of the incident was:

The incident involving the OY-JTY aircraft was caused by the extension of its expected flight time as a result of the adverse weather conditions that decreased the operational capacity of the Canary Islands airports. As a consequence, the aircraft landed at its alternate airport with 33 kg less than the minimum reserve fuel specified by the applicable regulations.

The CIAIAC analysed:

The investigation has highlighted the operational particularities of the Canary Islands airports as a whole, specifically, that the closure of one of the airports directly affects the others because their geographical location drastically limits the use of alternatives. This unique circumstance was highlighted in the event of flight JTG427, which took place on a day when the Canary Islands were being affected by a highly active front that was moving from west to east with two specific consequences:

- Firstly, it directly impacted the weather conditions at the airports, reducing their operational capacity (with the opening of low-visibility procedures and the cessation of activity in the manoeuvring area).

- Secondly, and as a result of the above, the accumulation of diverted traffic bound for other destinations led to a saturation of the airports’ stands, which eventually also diminished their operational capacity.

Meteorological forecast

The situation at the Canary Islands airports was generated by the passing of an extremely active Atlantic front that was moving from west to east and affected the entire archipelago. The front’s impact on operations increased throughout the day on 25/02/2018, reaching its most critical point at 15:00, with 3 of the 5 airports having to close.

AEMET had issued two special warnings in the two days prior (23 and 24), signalling the likelihood of generalised storms with the potential for high winds and heavy rain. These warnings were not used by the aeronautical community, which instead relies on specific meteorological information adapted to the requirements of the sector. The investigation has found that the aeronautical meteorological information was consistent with AEMET’s general warnings.

The adverse meteorology affected the lower surface levels (airports and approaches) but not the upper levels. Indeed, the information contained in the hazardous weather maps issued before the take-off of flight JTG427 ruled out hazardous meteorological phenomena en route. On the contrary, the TAFOR, which was the forecast most frequently used by the ATM services and the operator, predicted the following situation:

- At the aircraft’s scheduled time of arrival in the Canary Islands, the same conditions were expected at both the destination and the alternative airports.

- The expected conditions were:
+ strong-very strong and gusty winds, reduced visibility, rain and cloud cover.
+ moderate chance of storm activity.

Assessment of the meteorological conditions by the crew

Taking into account the previous conclusions (the three airports affected by the same conditions and the chance of storm activity), it would have been justifiable to load more extra fuel than the 500 kg loaded by the crew, which was enough to sustain an additional 15 minutes of flight.
There were no weight issues because the aircraft still had a margin of 3,000 kg both for take-off and landing before reaching the maximum weights. The review of the criteria applied for the flight found that the fuel planning was in line with both EASA’s regulations and Jet Time’s operating manual; therefore, normatively speaking, the planning procedure was adequate. However, the crew’s assessment of the forecasts at the destination and alternative airports was highly optimistic, being based on the hope that the adverse conditions would not affect all three islands simultaneously.

Assessment of meteorological conditions during the en-route phase

The crew’s handwritten notes on the operational flight plan confirm that as the aircraft was approaching the Canary Islands, they checked the actual meteorological conditions at different airports, both in Portugal and in the Canary Islands. At that time, the prevailing conditions at the Canary Islands airports were not causing any problems for their operations, which meant the aircraft could continue to its destination, passing the point where it would have been able to divert to the alternative route (LPFR).

The METARs show that the conditions began to worsen in the Canary archipelago after 13:30, with the situation becoming critical after 14:00. At this time, the aircraft was about to be transferred to the Canary Islands ACC (14:16). Furthermore, given that the situation had been managed satisfactorily until that point, the ATM services had not yet initiated flow control measures to prevent traffic from entering the ACC.

Therefore, the in-flight decisions taken by the crew were appropriate and consistent with the information available at the time.

Weather conditions in the Canary Islands upon the arrival of the aircraft

At 14:16, when the aircraft was transferred to the Canary Islands ACC, the meteorological conditions at its GCTS destination airport had begun to worsen, even if, meteorologically speaking, they were still sufficient for operations to continue (2,000 m visibility and 18 kt of variable wind). The problem was that the airport had accumulated a number of traffics on hold and had limited parking due to having received the diverted traffic from GCXO and some of the traffic from GCRR for two hours.

In the next 15 minutes (14:27), with the aircraft heading towards TFN and the storm front over the island of Tenerife, the conditions at GCTS began to deteriorate to the point of completely collapsing the airport. The torrential rain caused drainage problems, flooding and dragged various materials onto the runway and the manoeuvring area, which were then classed as contaminated. This situation, together with the decrease in visibility to less than 600 m, forced GCTS to close for two hours and declare rate 0. In light of this event, ENAIRE has taken measures to pre-assess the impact of heavy rainfall or extreme weather conditions, as was the situation in this case, on runways, manoeuvring areas and parking stands, in order to better anticipate impacts on operations at the Canarian airports in the future.

As a consequence, the situation in the Canary Islands at 15:00 was that 3 of the archipelago’s airports had been rendered inoperative by the meteorological conditions (GCRR, GCXO and GCTS). Only GCLP and GCFV remained open to traffic, although they were also operating at a reduced capacity due to having absorbed the traffic diverted from the islands’ other airports and the inclement weather (the front’s passage from west to east).

To summarise, flight JTG427 arrived in the Canary Islands at the most critical point of the day.

Management of the fuel emergency

As a result of the previously analysed meteorological and operational context, when flight JTG427 arrived, it was instructed to hold, initially, before proceeding to its original GCTS destination. When GCTS was subsequently closed and only two airports remained in operation in the entire archipelago, the aircraft had to continue in the holding pattern.

The aircraft’s flight time was extended by 42 minutes, with the entire flight lasting 6 hours and 7 minutes. From the moment they joined the holding pattern at TFN, the crew monitored the available fuel. This was demonstrated by their ATC communications at 15:17 (we are expecting minimum fuel) and 15:25 (In that case we will have to declare MAYDAY. Our fuel is up to 2 tons now). The records have shown that the actual amount on board was consistent with the amount reported to ATC.

The crew’s management during this holding period was adequate, monitoring the remaining fuel, keeping ATC informed of the fuel situation and, eventually, when it became apparent that they did not have enough fuel on board to comply with the minimum holding time, declaring an emergency with the term MAYDAY to obtain priority.

Following the aircraft's emergency notification, ATC, which was highly congested and saturated due to the ongoing situation, prioritised the JTG427 traffic over the other aircraft waiting to enter GCLP. They were given vectors to GCLP and the aircraft landed safely after making a stable approach to runway 21R. Despite being given priority, the aircraft landed carrying 33 kg less than the mandatory minimum amount of fuel.
In conclusion, both the crew and ATC managed the fuel emergency correctly.

The joint operation of the Canary Islands airports

The JTG427 incident has highlighted the fact that the geographical location of the Canary Islands airports means that in certain circumstances, such as the adverse meteorological conditions that affected this case, they function as a single unit. The sequence of events on 25/02/2018 demonstrated that the introduction of operational restrictions at two airports can eventually overload the others.

The number of available stands became an important factor in this event, limiting the operational capacity of airports that, meteorologically speaking, had no restrictions. The events have shown that activating the mass diversion plan, whatever the reason for doing so, directly affects the other airports in the archipelago. The measures adopted by ENAIRE (1.18.1) after the incident contain improvements in this regard.

Flow management measures during the event

The predicted meteorological conditions were known and considered in ENAIRE's “pre-tactical” phase and, as a result, mitigatory measures were put in place in the days prior to the event.

However, on the day of the incident, the situation did not develop as expected (the conditions were worse in the morning than in the afternoon). During the morning, operations proceeded normally, with only GCRR experiencing operational issues due to the meteorology. At 12:15, GCXO also began to have operational problems, declaring LVP procedures. Despite the implications that this began to entail for the other operating airports (impact on parking stands and holding times), the request to limit the traffic entering the Canary Islands ACC was not made until 15:00, when the situation had reached its most critical point.
Given the “isolated” geographical location of the archipelago and the consequent implications for the other airports, consideration should be given to an earlier implementation of flow control measures.

Metars Tenerife South:
GCTS 251700Z 27019KT 9000 -RA FEW015 BKN040 17/15 Q1001 NOSIG=
GCTS 251630Z 26016KT 9999 -RA FEW015 BKN070 17/14 Q1001 NOSIG=
GCTS 251616Z 27015KT 9999 FEW010 BKN070 18/15 Q1000 NOSIG=
GCTS 251600Z 26012KT 230V290 6000 -RA BKN006 BKN020 16/16 Q1001 RERA NOSIG=
GCTS 251537Z 24016G27KT 200V260 0600 +RA FEW002 BKN005 BKN015 17/16 Q1001 BECMG 9999 NSW=
GCTS 251530Z 23014KT 200V270 1000 +RA FEW002 BKN004 BKN020 18/17 Q1001 NOSIG=
GCTS 251500Z 24017G28KT 200V290 0800 +RA FEW002 BKN006 BKN013 17/17 Q1002 NOSIG=
GCTS 251435Z 22019KT 200V260 0600 +RA FEW004 BKN008 BKN013 17/17 Q1002 NOSIG=
GCTS 251430Z 22015G25KT 200V260 0800 +RA FEW004 BKN008 BKN013 18/17 Q1002 TEMPO 0700=
GCTS 251408Z 22017KT 2000 RA FEW004 SCT008 BKN013 18/17 Q1003 TEMPO 1400=
GCTS 251400Z 22018KT 2000 -RA FEW009 BKN011 18/17 Q1003 TEMPO RA=
GCTS 251352Z 22018KT 190V250 4000 RA FEW010 BKN013 18/17 Q1003 TEMPO 2000 RA=
GCTS 251330Z 21016KT 8000 -RA FEW010 BKN017 BKN040 19/17 Q1003 NOSIG=
GCTS 251300Z 22016KT 9999 FEW010 SCT017 FEW030TCU BKN040 19/16 Q1004 NOSIG=
GCTS 251230Z 22014KT 190V250 9999 FEW010 BKN017 BKN035 19/16 Q1005 NOSIG=
GCTS 251200Z 23012KT 200V260 9999 FEW010 BKN017 19/16 Q1005 NOSIG=
GCTS 251130Z 24012KT 9999 FEW014 BKN017 19/16 Q1005 NOSIG=
GCTS 251100Z 25011KT 210V280 9999 FEW015 BKN025 BKN050 19/15 Q1006 NOSIG=

Metars Las Palmas:
GCLP 251800Z 20024G39KT 9999 -RA FEW009 BKN025 18/16 Q1000 RERA BECMG 4900 RA=
GCLP 251747Z 20026G36KT 4500 2000S RA BKN010 BKN020 18/17 Q1000 NOSIG=
GCLP 251730Z 20029G39KT 8000 BKN008 BKN020 18/17 Q1000 RERA BECMG 4900 RA=
GCLP 251720Z 20031G45KT 8000 -RA BKN008 OVC020 18/17 Q1000 RERA BECMG 4900 RA=
GCLP 251708Z 20031G44KT 1200 R03/0750N R21/1700D RA BR BKN008 BKN015 18/17 Q1000 NOSIG=
GCLP 251700Z 20031G44KT 2500 RA BKN009 BKN020 18/17 Q1000 BECMG 1000 RA=
GCLP 251651Z 20031G44KT 8000 3500W -RA BKN009 BKN020 19/16 Q1000 BECMG 3000 RA=
GCLP 251630Z 20028G41KT 6000 -RA FEW008 BKN012 BKN018 19/17 Q1001 BECMG 4900 RA=
GCLP 251600Z 20029KT 9999 BKN012 BKN018 19/16 Q1001 RERA BECMG 4900 RA=
GCLP 251545Z 20028G43KT 160V230 7000 2000W RA BKN012 OVC018 19/16 Q1001 BECMG 4900=
GCLP 251530Z 20027G37KT 9999 BKN013 OVC020 19/16 Q1002 NOSIG=
GCLP 251508Z 20024KT 9999 4500NW -RA BKN012 OVC025 19/16 Q1002 NOSIG=
GCLP 251500Z 20026KT 9999 SCT012 BKN030 19/17 Q1002 NOSIG=
GCLP 251430Z 19024G37KT 9999 SCT013 SCT025 BKN035 20/16 Q1003 NOSIG=
GCLP 251400Z 20023G33KT 9999 SCT015 BKN025 BKN040 20/16 Q1004 NOSIG=
GCLP 251330Z 20024KT 9999 FEW015 SCT025 BKN040 20/16 Q1004 NOSIG=
GCLP 251300Z 20025KT 9999 FEW015 SCT025 BKN040 20/17 Q1004 NOSIG=
GCLP 251230Z 21016KT 9999 -RA FEW015 BKN040 19/17 Q1005 RERA NOSIG=
GCLP 251219Z 21022G34KT 2500 RA FEW015 BKN020 BKN040 18/16 Q1005 BECMG 9999 NSW=
GCLP 251211Z 21021G31KT 4500 2000S RA FEW020 SCT030 BKN040 18/16 Q1006 NOSIG=
GCLP 251200Z 20021KT 9999 FEW015 SCT040 20/16 Q1005 NOSIG=
GCLP 251130Z 21019G30KT 180V240 9999 -RA FEW015 SCT025 BKN040 19/17 Q1006 NOSIG=
GCLP 251100Z 20020G31KT 9999 -RA FEW015 SCT025 19/16 Q1006 NOSIG=
Incident Facts

Date of incident
Feb 25, 2018

Classification
Incident

Airline
Jet Time Finland

Flight number
JTG-427

Departure
Aalborg, Denmark

Destination
Tenerife South, Spain

Aircraft Registration
OY-JTY

Aircraft Type
Boeing 737-700

ICAO Type Designator
B737

This article is published under license from Avherald.com. © of text by Avherald.com.
Article source

You can read 2 more free articles without a subscription.

Subscribe now and continue reading without any limits!

Subscribe now
Are you a subscriber? Login
Subscribe

Read unlimited articles and receive our daily update briefing. Gain better insights into what is happening in commercial aviation safety.

Compare our plans

Send tip

Support AeroInside by sending a small tip amount.

Send tip

Related articles

Newest articles

Subscribe today

Are you researching aviation incidents? Get access to AeroInside Insights, unlimited read access and receive the daily newsletter.

Pick your plan and subscribe

Partner

Blockaviation logo

A new way to document and demonstrate airworthiness compliance and aircraft value. Find out more.

ELITE Logo

ELITE Simulation Solutions is a leading global provider of Flight Simulation Training Devices, IFR training software as well as flight controls and related services. Find out more.

Blue Altitude Logo

Your regulation partner, specialists in aviation safety and compliance; providing training, auditing, and consultancy services. Find out more.

AeroInside Blog
Popular aircraft
Airbus A320
Boeing 737-800
Boeing 737-800 MAX
Popular airlines
American Airlines
United
Delta
Air Canada
Lufthansa
British Airways