Fuel requirements

Yes. 45 minutes even if flying to the desert. You do get relief from needing an alternate though if it's VFR so there's something.... (Disclaimer: not in Canada)
 
But if you are ahead of schedule, say you have made 30 minutes with a tailwind, you can re-file in the air and extend your range to another airport 30 minutes more distant..
 
You wouldn't re-file. You'd just tell ATC that you're changing your destination. But now that you're changing the plan you start over with the rules and now need to plan to land at the 'new' destination with 45 minutes of fuel.
 
skylanerg said:
From a recent local incident of fuel starvation - If one files IFR yet the destination wx is forecast/actual VMC do the IFR minimum fuel requirements still apply?
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You might want to start your study on this subject with 91.167 and 91.169.


The requirement for 45 minutes reserve fuel on IFR flights does not change regardless of the destination weather. On all IFR flights, you must depart with enough fuel to get to the destination and then the filed alternate, plus 45 minutes reserve. Remember, you must have an alternate on your flight plan for all IFR flights unless:
  1. The destination is forecast to be 2000-3 or better for 1 hour before to 1 hour after planned arrival time, and
  2. The destination airport has an instrument approach you can fly.
If an alternate is not requied, then you need only have fuel to the destination, but you still need the same 45 minutes reserve fuel.
 
Captain said:
Yes. 45 minutes even if flying to the desert. You do get relief from needing an alternate though if it's VFR so there's something.... (Disclaimer: not in Canada)
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"VFR" isn't enough -- it must be 2000-3 for one hour either side of your ETA, and there must also be an instrument approach at your destination. If both conditions aren't met, you must file an alternate.
 
skylanerg said:
From a recent local incident of fuel starvation - If one files IFR yet the destination wx is forecast/actual VMC do the IFR minimum fuel requirements still apply?

Steven
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Yes, you are operating under the rule, not the condition, the best of my recollection, which admittedly is suspect, even under those conditions you need 45 min reserve on your destination. I do not believe you need to add the alternate though. It's been many years since I filed to depart IMC. A couple times I had to pop through on an enroute clearance, typically I wait for VFR to depart. Works out for me, YMMV.
 
kgruber said:
But if you are ahead of schedule, say you have made 30 minutes with a tailwind, you can re-file in the air and extend your range to another airport 30 minutes more distant..
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Sure. But you still must have 45 minutes reserve fuel based on your new destination when you re-file. Note that the regulation:
Sec. 91.167

Fuel requirements for flight in IFR conditions.

(a) No person may operate a civil aircraft in IFR conditions unless it carries enough fuel (considering weather reports and forecasts and weather conditions) to--
(1) Complete the flight to the first airport of intended landing;
(2) Except as provided in paragraph (b) of this section, fly from that airport to the alternate airport; and
(3) Fly after that for 45 minutes at normal cruising speed or, for helicopters, fly after that for 30 minutes at normal cruising speed.
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...says "operate," not depart. This is different from the VFR rule which only says "begin a flight."
Sec. 91.151

Fuel requirements for flight in VFR conditions.

(a) No person may begin a flight in an airplane under VFR conditions unless (considering wind and forecast weather conditions) there is enough fuel to fly to the first point of intended landing and, assuming normal cruising speed--
(1) During the day, to fly after that for at least 30 minutes; or
(2) At night, to fly after that for at least 45 minutes.
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Thus, any time you end up in the air under IFR with less than 45 minutes of reserve fuel, either you have an emergency or you broke 91.167.
 
Henning said:
Yes, you are operating under the rule, not the condition, the best of my recollection, which admittedly is suspect, even under those conditions you need 45 min reserve on your destination. I do not believe you need to add the alternate though.
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There is no exception in 91.167 to the requirement for an alternate based on re-filing in flight. If your new destination doesn't meet the two-pronged test, you must still have fuel to a suitable alternate plus reserve, not just 45 minutes reserve at the new destination. The operative word in that reg is "operate" as opposed to "begin a flight" in the VFR fuel reg.
 
Ron Levy said:
"VFR" isn't enough -- it must be 2000-3 for one hour either side of your ETA, and there must also be an instrument approach at your destination. If both conditions aren't met, you must file an alternate.
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Yes, the 1-2-3 rule is applicable. I was just being short because the OP was asking such a basic question I didn't want to get too detailed. Mine was the short answer, yours the 'more correct'.


Ron Levy said:
There is no exception in 91.167 to the requirement for an alternate based on re-filing in flight. If your new destination doesn't meet the two-pronged test, you must still have fuel to a suitable alternate plus reserve, not just 45 minutes reserve at the new destination. The operative word in that reg is "operate" as opposed to "begin a flight" in the VFR fuel reg.
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As long as your going to bust my balz on the previous I'll mention that you don't always need 45 minutes reserve under IFR. Some operations (International Flag) only require 30 minutes plus 10% time enroute.

And just to make sure everyone knows I'm not getting all angsty here I'll put a little smiley face:

----> : ) <----
 
Ron Levy said:
There is no exception in 91.167 to the requirement for an alternate based on re-filing in flight. If your new destination doesn't meet the two-pronged test, you must still have fuel to a suitable alternate plus reserve, not just 45 minutes reserve at the new destination. The operative word in that reg is "operate" as opposed to "begin a flight" in the VFR fuel reg.
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Right, so what is this two prong test requirement to which you refer? IIRC, and I openly admit, I'm hazy from disuse; If there is sufficient weather and forecast at destination I do not have to file or add alternate fuel; or am I mistaken? I don't fly IFR anymore so I don't really pay attention.
 
It's not a two pronged test...it's starting over with the flight planning. When you change your destination enroute you are required to have ALL the requirements as if you were departing from the ground.

You need to know the Wx and Notams...You need an alternate if the Wx requires it (1-2-3 rule) you need fuel to fly to the new destination plus 45 min if an alt is not required and to the destination and alternate plus 45 if you do....that means you may need to find an alternate.

It's not a 'two pronged test' it's a whole new flight that requires all the planning and requirements as if you were launching into the soup for the first time.

If you divert in flight to a new destination with marginal weather and then have to go missed and proceed to you 'new' alternate and then find out you cant get in because the ILS has been out of service for a week and has been NOTAM'd as such and then are forced to declare an emergency and get priority handeling to 'stick in into some field' in front of a bunch of airliners then you are GOING to be violated.

I am not saying you can't change your alternate. I do it all the time. But Wx and Notams and required fuel are a part of it. I use FSS and the SatPhone to company Dispatch to get everything I need. In a small single piot GA plane it'd be a lot more work.
 
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Not my scenario, here's what I was considering. Departing Long Beach in the morning, marine layer 600'-1600', IFR/IMC deck to the pass, I could slip under along the highway and through the pass, but why? I'm heading to Vegas or Phoenix, severe clear VFR forecast for the next 7 months. Do I only need to file with 45 minutes fuel to destination or do I need to file with fuel for destination, alternate and 45minutes?
 
If your destination is solid VFR for 7 months (a bit more that an hour before and after arrival time) why would you need an alternate? (Canada excluded)
 
For me, I need a takeoff alternate any time I takeoff from an airport that is below minimums to land. So if I take off in 1/4 mile down to 600 feet (RVR) then I need a takeoff alternate. If, in that situation, I'm going to Vegas which won't see a cloud for seven months I need a takeoff alternate but no landing alternate.

Get my point? Yes, you can launch into the soup with no alternate. It's based on destination weather and that comes from the TAF. No TAF then no Wx and now you need an alternate. KLAS has a TAF so 99.99% of the time you'd be good to go.
 
Captain said:
If your destination is solid VFR for 7 months (a bit more that an hour before and after arrival time) why would you need an alternate? (Canada excluded)
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That was my question...:dunno:

From a recent local incident of fuel starvation - If one files IFR yet the destination wx is forecast/actual VMC do the IFR minimum fuel requirements still apply?

Steven
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My answer was simple, you need to follow IFR rule since you are departing IFR but you only need 45 minutes from your destination with no extra alternate fuel required. That was how I remembered the rule for that situation.
 
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Captain said:
For me, I need a takeoff alternate any time I takeoff from an airport that is below minimums to land. So if I take off in 1/4 mile down to 600 feet (RVR) then I need a takeoff alternate. If, in that situation, I'm going to Vegas which won't see a cloud for seven months I need a takeoff alternate but no landing alternate.

Get my point? Yes, you can launch into the soup with no alternate. It's based on destination weather and that comes from the TAF. No TAF then no Wx and now you need an alternate. KLAS has a TAF so 99.99% of the time you'd be good to go.
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No sweat, take off alternate I'll be fuel heavy anyway. This was about figuring out how much destination fuel was required in a simple IFR departure to VMC, not Transpac budget fuel packing methods of manipulating the system (not that I object to doing it, it makes great sense not to haul fuel you don't need in revenue ops).
 
I was just making the point it's possible to take off with a takeoff alternate and not a destination alternate.
 
Captain said:
As long as your going to bust my balz on the previous I'll mention that you don't always need 45 minutes reserve under IFR. Some operations (International Flag) only require 30 minutes plus 10% time enroute.
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That is going to be more than 45 minutes, not less.
 
Henning said:
Not my scenario, here's what I was considering. Departing Long Beach in the morning, marine layer 600'-1600', IFR/IMC deck to the pass, I could slip under along the highway and through the pass, but why? I'm heading to Vegas or Phoenix, severe clear VFR forecast for the next 7 months. Do I only need to file with 45 minutes fuel to destination or do I need to file with fuel for destination, alternate and 45minutes?
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Depends on the weather at destination, not point of departure.
 
Henning said:
As I said, severe clear for the next 7 months, it's April in Vegas....
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Then as long as your destination airport has an approach you can fly, it doesn't matter what the weather is at Long Beach -- no alternate is required.
 
Captain said:
It's based on destination weather and that comes from the TAF. No TAF then no Wx and now you need an alternate. KLAS has a TAF so 99.99% of the time you'd be good to go.
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Not sure if you're just talking about the KLAS scenario or more generally, but I've always wondered about what forecasts exactly are acceptable for the purposes of the regulation. 91.167 says 'appropriate weather reports or weather forecasts' (same language in 91.169). Insisting on having a TAF would be a reasonable and conservative strategy, but doesn't seem to be explicitly required. I looked for a LOI since there are lots on the fuel requirements question, but couldn't find anything specific on this.

Not too familiar with the 121 / 135 regulations or what you fly, so if you're talking about those, or company procedures, ignore me.
 
Henning said:
So the answer to the OP is you need fuel to destination + 45?
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Insufficient data. The OP just said e destination weather was "VFR," which could be much less than 2000-3. Also, the OP didn't say whether the new destination had an approach he could fly. Thus, no specific answer is possible.
 
Captain said:
It's based on destination weather and that comes from the TAF. No TAF then no Wx and now you need an alternate. KLAS has a TAF so 99.99% of the time you'd be good to go.
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Perhaps that's the rule in your ops specs, but for Part 91 ops, if there is no TAF, you can use the Area Forecast (FA) to check for 1-2-3 weather. In fact, DUATS even tells you "No TAF available, refer to Area Forecast."
 
Yeah, the FA argument has come up. It does apply to my operation.

The classic example is KPWK. It about 13 miles North of Chicago O'Hare and does not have a TAF. Many times the Wx is CAVU and we're trying to hit it from long range and adding fuel for an alternate forces a fuel stop.

Guys will launch with just the FA showing VFR. I don't have a problem with it and think its legal. But then you get into shades. Not IFR, but not blue skies either. For my money I'd just assume have the TAF and be done with it. If I'm going to KPWK I just file ORD or DPA as the alt and call it good. If fuel is an issue then I may have to break out the FA, but it better be blue skies or I'm making a fuel stop.
 
Captain said:
Yeah, the FA argument has come up. It does apply to my operation.

The classic example is KPWK. It about 13 miles North of Chicago O'Hare and does not have a TAF. Many times the Wx is CAVU and we're trying to hit it from long range and adding fuel for an alternate forces a fuel stop.

Guys will launch with just the FA showing VFR. I don't have a problem with it and think its legal. But then you get into shades. Not IFR, but not blue skies either. For my money I'd just assume have the TAF and be done with it. If I'm going to KPWK I just file ORD or DPA as the alt and call it good. If fuel is an issue then I may have to break out the FA, but it better be blue skies or I'm making a fuel stop.
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Since the TAF is only valid for a 5-mile radius around ORD, and PWK is 13 miles away, you can't use the ORD TAF to determine that you don't need an alternate for PWK. However, because the FA is valid for PWK, your "guys" are legal launching to PWK without an alternate if the FA shows 2000-3 or better +/-1 hour.

That said, if the FA says 3000-5, and the ORD TAF says 300-1/2, I'd be hauling some extra gas on my run to PWK even if the FAA doesn't say I have to. Ditto going into ORD with the TAF saying 3000-5 and the FA saying 300-1/2. Consider it my conservative nature. :wink2:
 
I didn't see it mentioned here so I thought I might post..

In at least one POH the endurance tables calculate the aircraft's reserve endurance based on flying 75% power and then at 45% (or maybe 55%) power once you hit your reserve fuel. If you use the chart, you won't have enough fuel to meet the requirement of "45 minutes at normal cruising speed"
 
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dell30rb said:
In at least one POH the endurance tables calculate the aircraft's reserve endurance based on flying 75% power and then at 45% (or maybe 55%) power once you hit your reserve fuel. If you use the chart, you won't have enough fuel to meet the requirement of "45 minutes at normal cruising speed"
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I'm guessing they predate the change from "maximum endurance at 10,000 MSL" to "normal cruising speed." Anyone remember when they made that change? I know it was the old way when I got my IR in 1971, but I don't remember when it changed.
 
Ron Levy said:
Since the TAF is only valid for a 5-mile radius around ORD, and PWK is 13 miles away, you can't use the ORD TAF to determine that you don't need an alternate for PWK. However, because the FA is valid for PWK, your "guys" are legal launching to PWK without an alternate if the FA shows 2000-3 or better +/-1 hour.

That said, if the FA says 3000-5, and the ORD TAF says 300-1/2, I'd be hauling some extra gas on my run to PWK even if the FAA doesn't say I have to. Ditto going into ORD with the TAF saying 3000-5 and the FA saying 300-1/2. Consider it my conservative nature. :wink2:
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I know. I launch to PWK all the time with ORDs TAF...but each and every time I file ORD (or DPA) as the alternate.
 
Ron Levy said:
I'm guessing they predate the change from "maximum endurance at 10,000 MSL" to "normal cruising speed." Anyone remember when they made that change? I know it was the old way when I got my IR in 1971, but I don't remember when it changed.
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Possibly - here is a 152 manual POH that uses the calculation I mentioned. I've seen it in other POH's as well. If you're using info from a table, make sure you know how its calculated! It says something like 'reserve fuel is based on 45 minutes calculated at 45% bhp and is 2.8 gallons'. Definitely a detail you don't want to overlook.

http://www.langleyflyingschool.com/...andbooks/Cessna 152/Section 5 Performance.pdf

Page 9
 
Captain said:
I know. I launch to PWK all the time with ORDs TAF...but each and every time I file ORD (or DPA) as the alternate.
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You can never be wrong filing and carrying fuel for an alternate which meets the 91.163(c) requirements (as long as you don't exceed max gross weight :wink2:).
 
skylanerg said:
From a recent local incident of fuel starvation
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Mentioned in the NTSB probable cause of one of our club aircraft which crashed from fuel exhaustion was that the range of the aircraft is decreased by 7% without wheel pants. This is mentioned in fine print in the POH. Had the wheel pants been installed, the airplane would have had almost 30 minutes of fuel remaining (crashed just short of runway).

There were of course other issues with that incident as well.. but its important to pay attention to the fine print!

My personal rule is 1hr fuel but I get nervous even bumping up against that if the weather is anything but CAVU
 
Ron Levy said:
That's a 121 thing not applicable to normal Part 91 ops, where there is no takeoff alternate rule.
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I like the thought of a takeoff alternate, though I don't understand how you magically get your airplane to the alternate airport, w/o taking off from the one you're currently at. :idea:
 
COFlyBoy said:
I like the thought of a takeoff alternate, though I don't understand how you magically get your airplane to the alternate airport, w/o taking off from the one you're currently at. :idea:
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You fly it. The idea is to have somewhere reasonably close by to go if you have a problem after max abort speed but the weather isn't good enough to get back into your departure airport. It's mandatory for 121 operators in such conditions but up to the pilot's discretion for us regular Part 91 flyers.
Sec. 121.617

Alternate airport for departure.

(a) If the weather conditions at the airport of takeoff are below the landing minimums in the certificate holder's operations specifications for that airport, no person may dispatch or release an aircraft from that airport unless the dispatch or flight release specifies an alternate airport located within the following distances from the airport of takeoff:
(1) Aircraft having two engines. Not more than one hour from the departure airport at normal cruising speed in still air with one engine inoperative.
(2) Aircraft having three or more engines. Not more than two hours from the departure airport at normal cruising speed in still air with one engine inoperative.
(b) For the purpose of paragraph (a) of this section, the alternate airport weather conditions must meet the requirements of the certificate holder's operations specifications.
(c) No person may dispatch or release an aircraft from an airport unless he lists each required alternate airport in the dispatch or flight release.
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COFlyBoy said:
I like the thought of a takeoff alternate, though I don't understand how you magically get your airplane to the alternate airport, w/o taking off from the one you're currently at. :idea:
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You get there by taking off and going to your takeoff alternate.

The idea is the weather is below mins where you're at. If you lose an engine on takeoff after V1 you continue and the FAA wants to make sure you have a place to go that isn't 14 hours away. Takeoff alternate requirements vary slightly but as a general rule it needs to be no more than an hour away from your departure airport and needs to satisfy the same weather requirements as a normal alternate...ie 400/1 and 200 1/2 rule.
 
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