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Jetstream96

Why fuel plans does not contain missed approach fuel?

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In various operational flight plans, including the real-world ones and those from PFPX/Simbrief, there are trip fuel, contingency, holding fuel and extra fuel, etc. I cannot seem to find any of them with "missed approach fuel". I cannot understand why. If we do not plan any missed approaches, doesn't it mean that we have to divert to alternate if we make the first go-around? Because surely we will be already using reserve fuel at that time.

 

Or maybe it is included as extra fuel? 

 

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It is probably extra fuel.  Any doubts, add 5,000lbs more.

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Charlie Aron

Awaiting the new Microsoft Flight Sim and the purchase of a new system.  Running a Chromebook for now! :cool:

                                     

 

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MA fuel would be considered in FAR Reserve (US). FAR basic reserve 45 mins. It gets more complicated with Alternate requirements and Flag rules.

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Fuel for a missed approach is included in the diversion fuel.

 

According to EASA regulations, alternate fuel includes:

 

·      Fuel to fly a missed approach from the applicable MDA/DH at the destination aerodrome to the missed approach altitude, taking in to account the entire missed approach procedure

·      Fuel from the missed approach altitude to climb, cruise and descent to the alternate aerodrome from an en-route transition point using the expected arrival procedure

·      Fuel for the approach and landing at the alternate aerodrome

 


doesn't it mean that we have to divert to alternate if we make the first go-around?

 

Not necessarily. It depends why you have gone around.

 

If you went around simply because you were a bit late getting configured and failed to meet the stable approach criteria, if you have another go there chances are you will land without incident. You are not likely to be best served by going off to your alternate, arriving there with absolute minimum fuel (because you will now have burnt your diversion fuel and simply be left with your final 30 minute reserve) and, who knows, maybe you'll have to fly a missed approach there for some reason. Then you really will be in trouble.

 

If, however, you went around because the runway is blocked, or the visibility was poor and you couldn't get the required visual references, then you have to ask yourself - firstly, why did I only take minimum fuel on this sector when fog was forecast(!), and then how much chance do I stand of getting in if I try again compared to going to XXXX.

 

There is provision to 'commit' to your destination and burn your alternate fuel in the hold if you so desire (airlines may have restrictions on availability of runways, weather conditions etc). In addition, remember that just because you filed (and loaded fuel for) a particular alternate does not necessarily mean you have to go there if there is a closer suitable airfield, again giving you more options.

 

Ultimately, all the (EASA) law says that you must land with at least your 30 minute final reserve in the tanks. Beyond that, how you manage the fuel up to that point is up to you.

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Not necessarily. It depends why you have gone around.

 

If you went around simply because you were a bit late getting configured and failed to meet the stable approach criteria, if you have another go there chances are you will land without incident. You are not likely to be best served by going off to your alternate, arriving there with absolute minimum fuel (because you will now have burnt your diversion fuel and simply be left with your final 30 minute reserve) and, who knows, maybe you'll have to fly a missed approach there for some reason. Then you really will be in trouble.

 

If, however, you went around because the runway is blocked, or the visibility was poor and you couldn't get the required visual references, then you have to ask yourself - firstly, why did I only take minimum fuel on this sector when fog was forecast(!), and then how much chance do I stand of getting in if I try again compared to going to XXXX.

Thanks for the explanation. That makes sense. I am curious about the typical practice regarding taking extra fuel in case of go-arounds. I am sure when bad weather is expected, the captain or the dispatcher would add some extra fuel. But what happens if the weather is clear and no delay is expected at destination?

 

Suppose no extra fuel is added. In case of a go-around followed by a close of runway (due to an incident or whatever), they will probably burn some final reserve fuel on the way to the alternate. Wouldn't that be unsafe?

MA fuel would be considered in FAR Reserve (US). FAR basic reserve 45 mins. It gets more complicated with Alternate requirements and Flag rules.

If I understand correctly, those 45 min of final reserve fuel is never meant to be used under any circumstances. Otherwise it's an incident and needs to be investigated.

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I am curious about the typical practice regarding taking extra fuel in case of go-arounds. I am sure when bad weather is expected, the captain or the dispatcher would add some extra fuel. But what happens if the weather is clear and no delay is expected at destination?
 
Suppose no extra fuel is added. In case of a go-around followed by a close of runway (due to an incident or whatever), they will probably burn some final reserve fuel on the way to the alternate. Wouldn't that be unsafe?

 

You shouldn't be burning reserve fuel if your alternate fuel has been correctly calculated as above (includes fuel to fly a missed approach from the applicable MDA/DH at the destination aerodrome to the missed approach altitude, taking in to account the entire missed approach procedure).

 

Remember also that the law allows you to use your common sense. It says:

 

 

In-flight fuel management 

 

(1) The flight shall be conducted so that the expected usable fuel remaining on arrival at the destination aerodrome is not less than: 

(i) the required alternate fuel plus final reserve fuel; or 

(ii) the final reserve fuel if no alternate aerodrome is required. 

 

(2) If an in-flight fuel check shows that the expected usable fuel remaining on arrival at the destination aerodrome is less than: 

(i) the required alternate fuel plus final reserve fuel, the commander shall take into account the traffic and the operational conditions prevailing at the destination aerodrome, at the destination alternate aerodrome and at any other adequate aerodrome in deciding whether to proceed to the destination aerodrome or to divert so as to perform a safe landing with not less than final reserve fuel; or 

(ii) the final reserve fuel if no alternate aerodrome is required, the commander shall take appropriate action and proceed to an adequate aerodrome so as to perform a safe landing with not less than final reserve fuel. 

 

(3) The commander shall declare an emergency when the calculated usable fuel on landing, at the nearest adequate aerodrome where a safe landing can be performed, is less than final reserve fuel.

 

The law prescribes a minimum fuel requirement that covers a typical scenario (approach, go around, divert, land), but as I say, it cannot cover all scenarios. As the Captain, it is down to you to use your experience and judgement to load the an appropriate amount of fuel for the flight you are planning to undertake, taking in to account the likely possibilities.

 

A very important thing to remember (in aviation generally) is:

 

Just because something is legal does not mean that it is always safe.

 

Saying that, aviation is about risk management, and commercial aviation in particular is about balancing risk against commercial considerations. You could come up with all manner of scenarios -- what if the runway is closed, we divert and an aircraft has a parking brake failure on the runway when we're on final, for instance -- but you have to think also about how often does this happen? If everybody took an extra tonne of fuel every time they went flying just in case some of these far-fetched scenarios came to be, the airline would go bankrupt very quickly.

 

The minimum fuel requirement is:

  • Taxi fuel (APU usage, startup, taxi out - note that after touchdown at your destination you can burn as much as you want!)
  • Trip fuel (takeoff to touchdown)
  • Contingency fuel (usually a percentage of the trip fuel, but there are various ways of calculating and "optimising" this)
  • Alternate fuel (fly a missed approach at the destination, fly to the alternate, carry out an approach and land)
  • Final reserve fuel (30 mins holding at 1500ft)
  • Extra fuel as required by the Commander

Extra fuel could absolutely reasonably be zero -- nice weather, no delay expected (some airlines use statistics to calculate the contingency fuel for each flight which includes that used for typical holding as well) etc. It is not uncommon for crews to take just the fuel on the flight plan, which equates normally to the minimum legal fuel requirement. It is also perfectly safe -- again, how often do you divert? How often is a runway -- or two runways at two separate airfields -- blocked/closed at the same time? The probability is vanishingly small.

 

However, on another day -- fog or poor weather forecast at the destination, for instance -- extra fuel might be several tonnes (depending on the aircraft type). It is ultimately the Captain's responsibility -- that's why they get paid the big bucks!

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Thank you Simon. :) So basically it entirely depends the weather/traffic conditions, etc. I thought there were simpler rules, but it seems a lot more experience and judgements are at play here.

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No worries!

 

 

 


I thought there were simpler rules, but it seems a lot more experience and judgements are at play here.

 

Well, the rules themselves are pretty simple. However, in practice it is about more than just rules -- it is about airmanship as well.

 

For instance, let's say that you're flying from Paris to London Heathrow. The whole of the south of England is fogged in.

 

The law says you must take taxi fuel, trip fuel from takeoff to touchdown via the flight planned route, contingency fuel of (typically) 5% of the trip fuel, fuel to fly a missed approach at the destination, route to the alternate and land and final reserve fuel for 30 minutes at 1500 feet.

 

You could just take that and no more. It would be absolutely legal. But would it be safe, when you turn up and ATC tell you there's 60 minute holding delays for LHR, people diverting all over the place so all the nearby airports you could divert to are getting full and refusing to accept any more traffic etc?

 

That's where airmanship, judgement and experience comes in :)

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Don't interpret the rules the way LaMia did...  :Shame On You:

 

On a sensible note - thank you Simon for your insight. :cool:


Mark Robinson

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