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-   -   Jet goes down on its way to Medellin, Colombia (https://www.pprune.org/rumours-news/587574-jet-goes-down-its-way-medellin-colombia.html)

throwaway85 29th Nov 2016 14:05

The CityJet RJ's have wing and a center tank, max total fuel of around 9000kg, but not the aux tanks.

Fuel burn of a conservative 2T/hr, giving you 3.5h-4h + reserves. Cruises at 0.68-0.70. You would be able to lift 81 males + 9T fuel provided you had over about 1500-1800m runway at those temperatures.

So, if they filled it up to the gills they may have been approaching diversion fuel after 1600NM, but not running out. But then who knows how much they brought with them, or whether they's been able to get to panned cruise level, etc etc etc.

Anyhow, very sad.

M68 29th Nov 2016 14:15

Sky News: Brazilian football team's plane crashes in Colombia killing 76

"The head of Colombia's civil aviation agency, Alfredo Bocanegra, said reported comments from a female flight attendant that the plane had run out of fuel were being evaluated."

T28B 29th Nov 2016 14:28

Source = JACDEC:

The en-route altitude changed to 30,000 ft. before the pilots began their descent to Medellin at around 21:30L. The landing runway in use at the time was runway 36, meaning an approach from the south. It was dark at the time ... For reasons unknown the aircraft began to fly a holding pattern at 21.000 ft (FL210) near the Rio Negro VOR, about 17 miles southeast of their destination.
According to Colombia media, the pilots requested a holding because the flight experienced some kind of electrical problems. A minute later the pilots requested priority handling.
After one circle, the aircraft cancelled the holding and proceeded northbound its altitude gradually decreasing to 15,000 ft. before contact was lost.
The aircraft was found to have crashed against hillside in wooded, upsloping terrain ... Medellin is surrounded by mountains.
This report does not indicate that an emergency fuel state was declared. Whether or not fuel was related to the crew requesting priority handling is unclear.

The Ancient Geek 29th Nov 2016 14:35

The RJ85 can be fitted with 3 extra fuel options:- Panier tanks, a Rear Bay tank and a Front Bay Tank. Each option increases range at the expence of payload.
There is a graph here, 2016-11-28 LAMIA Avro RJ-85 crashed near Medellin with 81 on board » JACDEC scroll down about 1/3 of the document.

We do not know which tank options, it any, were fitted or how much fuel was actually loaded. It is also unclear whether the quoted ranges are with or without reserves but no sane pilot would have departed without reserves for a diversion plus 60 minutes so we must assume that some extra tanks were fitted.

The fuel theory is most likely a total red herring, expecially in view of the reported electrical problems.

All speculation is futile until we have more facts.

birmingham 29th Nov 2016 14:35


Originally Posted by The Ancient Geek (Post 9593131)
Yea right - the usual idiot speculation.
All will become clearer when we have some real facts. There are always a chain of contributing causes and the full story will not be known until the official report is published.

I think speculation that fuel management played some (though not maybe the primary causal role) her is inevitable rather than idiotic here and given the surviving wreckage should be a relatively straightforward task for the investigation. As usual FOD to the fans will indicate if the engines were running and the recorders will indicate the status of the fuel system,

But the speculation (and I agree it is that) is justified to a certain extent ...

If you know the 85 this 1600 nm mission is right at the end of the envelope so even with the correct calcs/weight/speed management they would have been under some time pressure if something went wrong on approach. Further those of you who know the A/C will be aware that the outboard (1 & 4) engines (fed from the outer wing tanks) are responsible for power generation while the APU is fed if I remember correctly from the inboard wing tanks. In normal circumstances the fuel system is very straightforward - set and go with the centre tank emptied first as usual. However in the event of fuel starvation anyone getting creative with the valves could also inadvertently create a situation where electrical power is lost as was initially reported (though not verified yet). Even if fuel starvation was not the cause of the reported malfunction Medellin is not the approach where I would want to deal with an electrical failure with limited hold/diversion options.

As people have correctly pointed out there are always multiple causes in incidents such as this and I would be very surprised if fuel management wasn't at least part of the problem.

2Donkeys 29th Nov 2016 14:39

The source of fuel starvation rumours, quite apart from any speculation here or elsewhere, appears to be a comment made by the surviving Flight Attendant, and reported by Sky News.

eagleflyer 29th Nov 2016 14:41

No CFIT without fuel, I guess.

If I understand right what I´ve found electrics on the RJ come from two generators (gone) plus the APU (gone) and a battery. No ram air turbine if I´m informed correctly. The hydraulics would have had to be provided by electrical power. I doubt battery alone would provide enough power for very long enough to provide hydraulics as well as keeping basic instrumentation going.
Flying only privately I would not consider planning to the absolute edge of my theoretical max performance or maybe beyond at night into a demanding airfield.

Martin_123 29th Nov 2016 14:43


Originally Posted by The Ancient Geek (Post 9593301)
The RJ85 can be fitted with 3 extra fuel options:- Panier tanks, a Rear Bay tank and a Front Bay Tank. Each option increases range at the expence of payload.
There is a graph here, 2016-11-28 LAMIA Avro RJ-85 crashed near Medellin with 81 on board » JACDEC scroll down about 1/3 of the document.

We do not know which tank options, it any, were fitted or how much fuel was actually loaded. It is also unclear whether the quoted ranges are with or without reserves but no sane pilot would have departed without reserves for a diversion plus 60 minutes so we must assume that some extra tanks were fitted.

The fuel theory is most likely a total red herring, expecially in view of the reported electrical problems.

All speculation is futile until we have more facts.

thanks for this.

According to avherald -
In the early morning hours of Nov 29th 2016 the CCAA reported, that an investigation has been opened into the crash, data and information are being collected. The head of investigation stated: "No existe evidencia de combustible en la aeronave" (there is no evidence of fuel in the aircraft).

A0283 29th Nov 2016 15:11


.The fuel theory is most likely a total red herring, expecially in view of the reported electrical problems.
Too early to say of course.

But there have been a number of high profile accidents in the past where the crew focussed on a (minor) technical issue and forgot properly monitoring fuel or speed.

Next to that accidents happen when multiple things go wrong. It is a series of events and not (as far as i have seen - never) a single cause.

IHF 29th Nov 2016 15:27


Originally Posted by FrontSeatPhil (Post 9593270)
As a frequent SLF on a chartered luxury RJ85, nine seems steep but not impossible. I usually see 5 or 6 for a passenger count of maybe 20 people.

Thanks FSP, good point (my SLF experience is on just regular scheduled ops, not charters)

dmba 29th Nov 2016 15:33

It's being reported here in Brazil that José Maria Córdova airport has stated that there was an electrical failure, notified by the aircraft.

dmba 29th Nov 2016 15:37

Of the six survivors, three are Chapecoense players. One of these has had a leg amputated in hospital and remains in a critical condition, with head trauma and injuries to his abdomen and thorax. Two other survivors, who were crew, are considered to have non-critical injuries. The other survivor is a journalist who is said be in a stable condition.

A fourth player who survived the crash has since died in hospital.

eagleflyer 29th Nov 2016 15:37

I saw a picture in some British paper that suggests the flight carried a second flightdeck crew. Might be an explanation.

PEI_3721 29th Nov 2016 16:06

eagle #49, incorrect.
The RJ has 2 engine driven generators (engs 1 and 4), and 1 (non essential) on the APU; this is the Normal power level.
AC and DC power can be supplied from a hydraulically powered generator (green system) from either of the 2 hydraulic systems (engs 2 and 3) via a power transfer system. This is the Essential level of power.
There is also a Std By static inverter from the battery (second optional) supplying the Emergency level flight instruments.

Thus the aircraft is exceptionally well supported electrically, enabling flight without any power generating systems.
All other airframe systems have sufficient redundancy to enable an emergency landing without any generated electrical power.

dmba 29th Nov 2016 16:18

Now saying that there were 77 people on board. 4 people on the list did not board the plane.
Crew: 9
Passengers: 68
Survivors: 6

Super VC-10 29th Nov 2016 16:29

Apparently the airline's owner was flying the aircraft and is one of the fatalities.

Accidente avión Chapecoense: El piloto del avión siniestrado también era el dueño de la aerolínea LaMia | Marca.com

ULMFlyer 29th Nov 2016 16:39

FWIW, on the Brazilian aviation forum Contato Radar, someone posted a picture of one of the engines showing little to no damage to the fan blades that are visible

swiftyb 29th Nov 2016 16:47

Football
 

Originally Posted by dmba (Post 9593394)
Now saying that there were 77 people on board. 4 people on the list did not board the plane.
Crew: 9
Passengers: 68
Survivors: 6

I would hazard a guess at the possibility of a few "extra crew" hopping on board to get to watch the football match.

eagleflyer 29th Nov 2016 16:47

PEI, but where does hydraulic power come from when all engines have failed and the APU doesn´t run due to lack of fuel? I understand it would come from an electrical pump that would run on battery power (the only energy source left). How long would that battery last?

dmba 29th Nov 2016 16:51

This was not a charter flight. It was a commercial flight. ANAC, the Brazilian aviation authority, did not auhtorise the team to take charter flight from Sao Paulo to Medellin. This decision caused the team to be delayed 2 hours before leaving Sao Paulo and resulted in the connection in Bolivia. The decision was not the responsibility of LaMia.

crg28 29th Nov 2016 17:00

WRONG!

It was a Chartered Flight from BOLIVIA to COLOMBIA.

The flight from Brazil to Bolivia was commercial....but this was a different flight. ANAC didn't allow the chartered flight from Brazil to Colombia because the charter plane/company was from Bolivia and not from Brazil or Colombia. So the team flew to Bolivia first on a commercial flight....

Please stop posting bad information here.

akaSylvia 29th Nov 2016 17:08

https://pbs.twimg.com/media/CycjbqYXUAAW7AL.jpg

SeenItAll 29th Nov 2016 17:11

As noted, there have been at least two significant crashes in which FC concerns about what eventually proved to be minor electrical issues caused sufficient distraction to result in fuel exhaustion and a crash right before landing. The particular ones that I recall are a United DC8 in Portland, Oregon and a Eastern L1011 at Miami. But I am sure there are others.

DaveReidUK 29th Nov 2016 17:17


Originally Posted by eagleflyer (Post 9593432)
PEI, but where does hydraulic power come from when all engines have failed and the APU doesn´t run due to lack of fuel? I understand it would come from an electrical pump that would run on battery power (the only energy source left). How long would that battery last?

Why does that matter ?

The only powered primary flight control on the 146/RJ is the rudder; elevators and ailerons are controlled via conventional servo-tabs and will function perfectly well in the absence of hydraulic power.

PEI_3721 29th Nov 2016 17:47

eagle, # 62,
You are contemplating a situation involving failure of 4 engines or a combination of engines and the 4 independent power generating systems - no electrics, no hydraulics. Even then the battery should provide 30 min power, more with a dual option, enabling basic IFR flight; attitude, E2 compass, and pressure st by ASI and altimeter.

As DRUK explains above, flight control is not an issue.
IIRC Such a scenario was demonstrated during certification testing, ...

aterpster 29th Nov 2016 17:48

SeenItAll:


As noted, there have been at least two significant crashes in which FC concerns about what eventually proved to be minor electrical issues caused sufficient distraction to result in fuel exhaustion and a crash right before landing. The particular ones that I recall are a United DC8 in Portland, Oregon and a Eastern L1011 at Miami. But I am sure there are others.
The Eastern flight didn't run out of fuel. The crew was distracted by a landing gear indication issue. The F/O unintentionally applied slight forward pressure on his yoke, dropping the autopilot from command to control wheel steering. They slowly descended into the swamp.

The other big out of fuel was the Avianca 707 at JFK.

Trim Stab 29th Nov 2016 17:55


Apparently the airline's owner was flying the aircraft and is one of the fatalities.
I think that operations with aircrew who are financial stakeholders should either not be permitted or else be regulated so that the operating company has minimum cash reserves to survive a few non profitable flights. I used to fly charter aircraft in Europe in which the chief pilot was also part-owner and personally witnessed (and heard of others from colleagues) when his airmanship was outrageously compromised to save money when cash flow was difficult. On one occasion, rather than announcing a fuel emergency, he cancelled IFR to avoid a long low-level IFR approach and instead did a direct VFR approach in IMC - this was a EU/OPS charter with pax on board. On another occasion, he refused anti-ice protection on a departure in icing conditions because the cost would cause the flight to be non-profitable.

eagleflyer 29th Nov 2016 18:21

Thanks for your input. I was not aware that on this type only the rudder depended on hydraulics. So a controlled glide towards a runway would have been technically possible. As a controller I ask myself what I could have done to help a crew in such a situation. Will transponders usually be on the emergency battery bus? Othewise I´d have to rely on primary radar, and I heard management talking about "there´s no need for this nowadays".

birmingham 29th Nov 2016 18:27

Unfortunately it looks pretty clear this one ran out of fuel. Other than the don't speculate speculators and the wait for the enquiry bunch, does anyone think that there is a viable alternative explanation? No FOD fan distress, no fuel, no fire, no electrics, no go around, out of range. Of course there maybe a completely different explanation but this is a flyers forum folks. The 146 is not my favourite jet but its record over many years is that whatever its shortcomings it is a pretty safe beast. Fuel management must surely have had a role,

cargun 29th Nov 2016 18:32

Can someone interpret the Flightradar data?
The cruising speed was 676 km/h.
Seems like the auotopilot is deactivated at around 2:15 UTC (manually increasing speed ? to 700km/h) long before descent, may things start to go awry here?
2:33 UTC descent starts from 9144m to 7612m, maintaining speed. Is this normal?
2:36 UTC speed starts to decline as well, dropping to 441km/h in 11 minutes (2:47).
2:42-2:47 holding starts
2:47 UTC altitude 6400m speed 441km/h
2:50 Tries to speed up to 513km/h maintaining 6400m altitude
2:55 Speed drops to 263km/h, Altitude to 4740m and vanishes off the radar.

It has been reported that the airplane declared emergency at 10pm and crashed at 10:15pm Colombian time (3:15 UTC), so flying 20 minutes at around 260km/h off the radar? The crash site's altitude is around 2500-2600m.

The crash site here is reported as 17km away from the airport. https://t.co/qPKJMab7dA, it vanishes off the radar at around approximatley 30 km away from the airport. If the reported crash time and locations are correct this means flying 13km at an average speed of 153km/h. V0 is 263km/h. V-Crash 43km/h, hence the survivors?

If there were a fuel problem why hold 13 minutes? The holding may be for dumping fuel for an emergency landing...

alainthailande 29th Nov 2016 18:32

Are fuel gauges still alive when flying with minimal power from batteries?

Lonewolf_50 29th Nov 2016 18:37


Originally Posted by cargun (Post 9593522)
  1. 2:33 UTC descent starts from 9144m to 7612m, maintaining speed. Is this normal?
  2. 2:36 UTC speed starts to decline as well, dropping to 441km/h in 11 minutes (2:47).
  3. 2:42-2:47 holding starts
  4. 2:47 UTC altitude 6400m speed 441km/h
    2:50 Tries to speed up to 513km/h maintaining 6400m altitude
  5. 2:55 Speed drops to 263km/h, Altitude to 4740m and vanishes off the radar.
If there were a fuel problem why hold 13 minutes? The holding may be for dumping fuel for an emergency landing...

An intriguing question (why hold for 13 (or 11) minutes?) but your second question makes no sense for me. Why would they need to dump fuel for an emergency landing, given the discussion over how much fuel this aircraft can carry and how long the flight was? You don't need to be on empty/fumes to carry out an emergency landing, right?

Flight Safety 29th Nov 2016 19:06

Perhaps someone should be looking into the flight history of this pilot/airline owner who was flying the plane, to see how much recent experience he had. It's possible that he got distracted with an electrical issue and went into a race track pattern to troubleshoot, and while doing so, forgot about the fuel situation. Sounds like he was cutting the fuel situation close anyway.

Guy of Gisborne 29th Nov 2016 19:22

The 146/RJ can not dump fuel. If you want to reduce landing weight or fuel you have to burn it off.
Rather than looking at distance travelled, look at time airborne. On average the AC will burn 2000kgs per hour, taking into account take off, climb, cruise and descent. The AC took off at 2218z and disappeared at 0255z. That's a flight time of 4:37hrs and roughly 9000kgs of fuel burnt. The max useable fuel quantity is 9300kgs. Unless pannier tanks were added (I personally don't think this is a financially viable option for a South American operator buying a relatively cheap regional jet). This would increase useable fuel to 10300. The AC definitely declared an electrical emergency. Then continued to hold PRESUMEABLY to deal with the checklist etc. To have a electrical failure due to lack of fuel is an idiotic assumption as the immediate emergency would be the flameout of engine/s.

TriStar_drvr 29th Nov 2016 19:25

Dump fuel? Why would you dump fuel when you are damn near out? Here's the answer. This would be humorous but for the fact that dozens of people lost their lives.

Chapecoense plane crash: 75 dead and 6 survivors after plane carrying Brazilian football team crashes in Colombia - Mirror Online

neila83 29th Nov 2016 19:31

People PLEASE stop talking about dumping fuel. Pilots only dump fuel when above maximum landing weight, generally if there is a problem near the start of the flight! Not at the end of a flight near the edge of the plane's endurance. Even them, in a severe emergency pilots will just get it down and land above max weight. Narrow bodies dont generally even have fuel dump capability.

To add some local info (I live in Medellin) the weather last night was fairly vile and has been in general for a good couple of months, the wet season has been very strong, and long, this year.

If they (speculation) genuinely did take it to the limit with fuel planning that would have been extremely risky as you could easily be down an alley with nowhere to go if weather conditions weren't favourable. Colombian domestics carry a lot of reserve for holding and enough to get back to origin at this time of year - quite interesting watching on FR24 when the weather is bad in Bogota. You cannot rely on getting into your destination.

It hasn't been collaborated but someone on the 'other' forum mentioned that a vivacolombia flight called an emergency after attempting takeoff just before this one was due to land. If true that could explain having to hold with a bad fuel situation...not a good place to be.

klintE 29th Nov 2016 19:31

Is it possible that range was miscalculated?
I mean average passenger weight is possibly estimated on many types: men, women, kids etcetera.
But here we have the group only well built men so...
(And it really happend earlier; but can't help where and when it was)

Guy of Gisborne 29th Nov 2016 19:34

All that have flown RJ/146s (inc me) will tell you that fuel CANNOT be dumped from this AC.

neila83 29th Nov 2016 19:35

Just to add..that final ground speed of 142 knots is VERY low considering the altitude it was at...

plhought 29th Nov 2016 20:03

A lot of technical mis-understanding about this airframe so i'll try and summarize some technical tidbits here. Apologies if it appears hap-hazard - just going back through the thread.

- No fuel dumping provisions in the 146/RJ

- Fuel Qty indication is availible with only battery power. Infact, there's a momentary Fuel Qty pushbutton above the Engine Insturments that lets you check qty with battery off. It's a digital display on the bottom of the EIS.

- Pannier tanks can be installed and removed regardless if aircraft was delivered from factory with/without them. I suspect this one did not have any installed though, as it's a relatively big job and usually the entire (relatively small) operator community will get wind of someone looking for pannier tanks parts.

- Pannier(or auxillary) tanks are considered part of the wing tanks and thier qty indication is combined with wing tanks if installed. Also an annunciation if they are not empty on the overhead panel. Pannier tanks will feed into thier respective wing tanks.

- I highly doubt any of the belly aux tanks were installed in this aircraft. They are very rare and the only outfit that I know that uses them consistenly nowadays is the FAAM aircraft. Home

- Redundancy is king on this aircraft (it is British...). As detailed above a bit, electrical power is primarily derived from two 115/200 VAC generators on engines 1 and 4. The APU also drives an identical generator without the CSD. Each single AC generator is capable of completely powering the aircraft. In the Avro RJ, bus switching in the event of a generator failure is automatic (provided panel is configured correctly). There is no paralled AC buses in this aircraft. DC power is provided through two (optional third) Transformer Rectifier Units. 26VAC power through transformers for some avionics.

- Essential and Emergency (different buses on this aircraft) AC & DC power can be provided from: Battery (in conjunction with static inverter), and/or a hydraulically powered standby generator (Powered off green system - requires #3 engine-driven-hydraulic pump functioning. Isolates Green system)

- With emergency DC (battery) and AC (static inverter) only:
- Standby Horizon
- #1 VOR/ILS
- #1 COM
- #1 XPNDR
- Standby ASI and Altimeter (straight old pitot/static insturments - no DC draw)
- *I think* L/H landing light
- Pilot's Windshield wiper
- Yellow system DC pump (used to help extend yellow emergency extension jack on main gear, and pump up brake accumulator)
- Anti-skid (Anti-Skid sys. switch has to be placed in BATT position)
- EIS N2 indication
- EIS EGT indication
- FADEC continues to function (if engines are) through PMA's on the FADEC/HMU units on engines.

With Essential AC & DC (from Green system hydraulic stand-by generator)
- couple more engine indications
- More avionics
- normal cockpit lighting
- Battery is isolated w/ standby generator operating.

- Fuel system is a mix of complexity and simplicity.
https://s14.postimg.org/x1jxxj66p/BAe146_RJFuel_Sys.jpg

Anhedral wings will make fuel in the wing tanks go outboard through gravity. Gravity & jet transfer pumps flow fuel from wing tanks to Inboard and Outboard feed tanks in each wing. Inboard for #2/3 engine - Outboard for #1/4. AC pumps in each feed tank provide jet-transfer pump pressure and pressure fuel to engines. Engines will suction-feed fine from feed-tanks though as well.
Center-tank fuel will flow into wing tanks. Floats in each feed tank will annuciate a low fuel condition if any tank is less than full (~600 lbs each).

- In the event of an AC electrical failure, standby hydraulically driven fuel pumps can provide fuel pressure.

- Primary flight controls with exception of rudder are completely manual with flying/servo tabs.
- Loss of yellow hydraulics means no roll spoilers, and some ground spoilers
- Loss of green means no speed-brake, other ground spoilers, and primary gear extension.
- Flaps can run half-speed off a single (yellow or green) hydraulic system.
- Alternate gear extention is gravity, with an emergency-yellow assister-jack for the main gear that may be powered from Yellow DC pump.

It is typical operator method to have APU running below 10,000 ft, providing bleed air for AC packs and pressurization. Frees up bleed air from the anemic engines (LF507). The APU Gen switch will usually be left on, although it will not be on either bus. In event of Gen failure with APU Gen on, APU gen will power the failed bus. APU running does jump into your fuel usage a bit though too...

Having said all this.....this redundancy is very suspect when you have no fuel....


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