The first thing to say, is thank the Gods and fate that nobody was killed.
If the flight had been “authorised” by someone other than the Commander, that someone showed a distinct lack of management come Airmanship skills in allowing the flight to depart with half-tanks, knowing, or ought reasonably to have known, the aircraft would arrive back O/H Shoreham with less than what HIS own FOB said it should arrive back with.
What “Authorisation” process did this chap employ – Mickey Mouse’s ?
That the PIC (even a PPL with very limited experience, never mind twin-time) did not ‘twig’ that having filled the machine to half-full (FOB intended at departure 60 US galls) yet in evidence noted after refuelling the Left Tank said “FULL” and the Right Tank said “3/4” - was not too bright for a man with a superior brain - regardless of previous tech log entries he may or not persued.
His intent was that the aircraft departed with
HALF its FM quoted TOTAL fuel capacity (128 inc 5 unusable). It did not; even after taking note of the stupid wish of the Clubs management that he returns the aircraft with basically minimum fuel, that should have triggered a warning sign that something was amiss at this early stage ….
eg
I’m departing with the aircraft indicating nearly FULL tanks……..how do I get back with basically minimum fuel using my 20 gal/hr Rule of Thumb for a round trip of 2 hrs (plus 2 mins) ?
It was never going to work if he was to please the idiot who “authorised” the flight.
What does this brain surgeon do in his theatre when an oxygen bottle says “FULL” knowing he’s been operating for 6 hours ?
AAIB Report excerpts with my comments in
RED.
Ref :
http://www.dft.gov.uk/stellent/group...ty_502314.hcsp
After refuelling the pilot noted that the fuel gauges indicated 'full' on the left and 'three quarters full' on the right.
As the aircraft passed through the Shoreham overhead, the pilot began a shallow left turn and started to carry out the Pre-Landing checks. As he did so he noted that the fuel gauges indicated 'half full' for the left wing tanks and a 'quarter full' for the right tanks.
Was that the one and only check he did of FOB ?
In the limited time available the pilot was unable to refer to the emergency checklist during the restart attempts and he cannot recall whether he selected the AUX fuel pump to HI in accordance with the checklist.
Flying solo and having an engine failure, there’s not much spare metal capacity to confirm by check-list your “Engine Failure” drills.
at about 400 feet and pointing directly at the airfield, the pilot realised that he would be unable to glide to the runway and he began looking for a suitable place to land.
It’s a bit late at 400 feet looking for a suitable place to make an emergency landing.
The total fuel capacity is 128 US gallons, with 5 US gallons unusable.
So if you want to depart with HALF tanks……..why accept the situation that tells you the machine is only a quarter of a tank away from MAX fuel load ?
Fuel planning
The evening before the flight the pilot had carried out his navigation planning using a computer based navigation planning aid.
The computer was programmed to assume zero wind for the route and a cruising true airspeed (TAS) of 154 kt with a fuel consumption of 25.5 US gallons per hour (GPH). The computer printout of the plan, which the pilot took with him on the flight, showed a total flight time for the return trip of 2 hrs and 2 minutes and a fuel burn of 52 gallons.
The pilot later stated that he did not rely on his computer programme for fuel calculations but used a 'rule of thumb' rate of fuel consumption of 20 US GPH which had been given to him by instructors during his type conversion training.
The PIC was certainly ‘let down’ by these “instructors” giving him duff gen which was NOT on the side of safety.
He was also aware that G-OMAR was occasionally used for charter flights and that in order to avoid potential weight problems the aircraft operator had an unwritten policy that the aircraft should not be returned with very high residual fuel loads.
As has been said by others, this policy should NEVER deter any PIC of what fuel HE wants over-head.
Accordingly, the pilot calculated he would need 40 US gallons for the 2 hour flight plus 10 US gallons reserve giving a total requirement of 50 US gallons. The pilot further stated that he was in the habit of converting the US gallon figure to Imperial gallons to provide an extra safety margin. Thus for this flight he planned to have 50 Imperial (60 US gallons) on board for the flight.
Fair enough. Having taken into account this logic, it is disappointing to know a mental process failed in further logic after the refuel operation.
Fuel uplift
The aircraft technical log indicates that 30 US gallons remained on board after the previous flight, but the pilot states that he based his uplift calculation on 30 Imperial gallons (36 US gallons) remaining.
To achieve his planned total fuel of 50 Imperial gallons (60 US gallons) the pilot calculated that he needed to load a further 20 Imperial gallons (24 US gallons); he therefore requested the refueller to load 45 litres (12 USG) in each wing tank.
The pilot was unable to explain why he had indicated in the aircraft technical log that he would uplift a total of 30 USG.
If there was 30 US on board already, he needed another 30 to make the FOB 60 he wanted, that is what he planned to depart with. No ?
the fuel gauges in the Seneca III provide a general indication of fuel on board but cannot be relied upon for fine tolerance readings.
“FULL” and “3/4” Full are not noted for being fine tolerance readings.
with an evenly balanced fuel load of 50% or less the fuel is carried only in the two inboard tanks and there is therefore no fuel to be seen in the outboard tank.
Having noted 30 galls before refuelling, and wanting to depart with HALF the full capacity of the machine, it was very unfortunate the PIC did not have a look to verify what the gauges were telling him after the refuel.
If they were in any way reliable (forget fine tolerance readings) he would have seen fuel in the tanks.
The aircraft technical log has a record of arrival fuel, fuel uplift and fuel on board for each flight.
The aircraft had last been filled with fuel two weeks before the accident flight and a total of fourteen flights had been made prior to the aircraft's departure from Shoreham on 2 April 2001.
I cannot believe, having read about this dumb “unwritten” charter flight restriction on returning the aircraft with low fuel states, this machine actually flew 14 flights and NEVER refuelled.
Who would hire this twin (any twin) for anything less than 30 minutes ? So let’s say we have 7 hours flying and using that erroneous Rule of Thumb of 20 gal/hr that’s 140 gallons burnt off……… more than the damn thing can carry. Some Operations department ! Or am I reading this wrong ?
PA 34 qualified pilots of the operating company questioned during the investigation were all aware that the unwritten, but generally widely used consumption figure of 20 USG per hour was applicable to the 55% power settings.
General Aviation Safety Sense Leaflet 1C 'Good Airmanship Guide', published by the CAA, recommends that the AFM fuel consumption figures should be increased by 20% to allow for in-service wear.
The owners who hired this machine out obviously do not subscribe to the above publication.
The Flying Order Book (FOB) for the aircraft operating company requires pilots to take account of the fuel burn for the entire route plus five per cent and carry additional fuel to allow a diversion to a nominated alternate from overhead destination plus a further 45 minutes reserve. A fuel plan calculated in accordance with the AFM and the FOB and using Lydd as an alternate for the return flight shows a total fuel required for the return flight of 73 USG.
Having “Authorised” this flight, what steps did this gent take to ensure his own FOB was being followed ? Very small ones !
Safety Sense Leaflet 1C 'Good Airmanship Guide' recommends that pilots should 'plan to land by the time the tanks(s) are down to the greater of 1/4 tank or 45 minutes, but do not rely solely on the gauges which may be unreliable'.
The Safety Sense leaflet's fuel planning advice applied to the pilot's calculated fuel burn would have given a total fuel required of 71 USG.
I have not read that the PIC intended to follow this good advice – or that he was even aware of it.
FUEL PLANNING.
The pilot based his fuel plan on a 'rule of thumb' provided to him during his type-conversion training.
However, the pilot planned to fly at 154 kt TAS which the AFM indicates requires 23.3 USG per hour.
The pilot calculated his reserve fuel by adding 10 USG to the fuel burn and by adding a further safety factor by converting the final figure into Imperial gallons.
He thus planned to carry a total of 60 USG compared to the 73 USG that would have been required if the flight had been planned in accordance with the AFM and the FOB.
Any “Authorising” Officer worth his salt would know 60 US gallons were not going to be enough for this trip. A terrible management failure. Slack is not the word.
The pilot's fuel plan gave him less fuel than either the FOB or CAA recommend.....
it appears that the fuel on board prior to refuelling was at or very close to the 30 USG shown in the aircraft technical log.
Does not explain how the machine flew 14 trips without a refuel along the way !
Conclusion
The fuel on board prior to departure from Shoreham was at least 54 US gallons.
The actual fuel burned during the flight was approximately 55 USG.
It is therefore possible, but perhaps unlikely, that both aircraft wing tanks emptied within a few seconds of each other.
It seems more likely that the fuel remaining on board when the aircraft arrived overhead Shoreham was very low with perhaps slightly more in the right tank than the left.
At 90 kt the windmill RPM would have been above the maximum for starter motor engagement and the pilot's attempts to restart with the electric starter motor would have had no effect.
A lesson for all.
Running out of fuel can be fatal.
Running short of common sense likewise. I hope owners and operators brush-up on their FOB’s and eradicate stupid and negligent items, and those who plan to be PIC take careful note of this accident and its catalogue of pitfalls and bear traps.
TG
ps Edit was me spelling colour the real way instead of color for the UBBCODE