How many flight hours before you need a break because of mental or physical fatigue

  • less than 1 hour

    Votes: 0 0.0%

  • 1-2 hours

    Votes: 2 1.4%

  • 2-3 hours

    Votes: 37 26.1%

  • 3-4 hours

    Votes: 51 35.9%

  • 4-5 hours

    Votes: 20 14.1%

  • 5-6 hours

    Votes: 8 5.6%

  • 6-7 hours

    Votes: 5 3.5%

  • more than 7 hours

    Votes: 19 13.4%
  • Total voters
    142
D

diamond

Well Known Member
I'm curious what the in-flight threshold for fatique is for RV pilots. Let's be clear that I am NOT advocating pushing personal limits to the point where safety is compromised.

So how many hours can you fly before you feel the need to come down for a mental and/or physical break? If potty time or refueling are always the overriding limitation, then this poll is not for you. If you have never been airborn long enough to reach a point of mental/physical fatique, then this poll is not for you. Also, I'm interested in YOUR threshold, not that of your passenger(s).
 
Too many factors involved!

If the air is smooth, temperature is nice, no problem going 4-4.5 hrs.
In hot turbulence, sometimes 2.5 can be a grind.
 
Tough question to answer

Fatigue is such a multi-faceted issue its hard to pin down a good answer to this question. For me - on a perfect day and at my peak performance - I would out last the airplane. In the RV4 that was about 3 hours endurance.

On the second leg of the day, the seat became unbearable toward the end of the flight. So, perhaps about 5 hours in a day given all other factors optimized.

Finally, I might add that we're the worst judge of our own performance, relative to fatigue. NASA has a special team that's done much to study the issue. In my line of work, fatigue is our biggest enemy.
 
I do not understand what you want. I plan on max three hour legs for physiological relief but have had trouble with a two hour flight due to derriere fatigue.

I made an 11+ hour flight (total flying in one day) but that was about four legs. I also had a wing leveler autopilot which made that possible.
 
Ron Lee said:
I do not understand what you want. I plan on max three hour legs for physiological relief but have had trouble with a two hour flight due to derriere fatigue.

I made an 11+ hour flight (total flying in one day) but that was about four legs. I also had a wing leveler autopilot which made that possible.
Click to expand...

I'm talking about single legs, not multiple legs in 1 day. Don't over think the question here. I know there are situations where long sustained turbulence can add fatigue, but I'm referring more to common and mostly comfortable weather conditions with periods of mild to moderate turbulence thrown in occasionaly. My poll also assumes auto pilot use if that is your normal mode of operation on long flights.
 
I could easily handle 8 hours flying days in the Cherokee. That's how long it took to get from Texas to Oshkosh. Flying the Cherokee in good clear daytime VFR weather is not very fatiguing at all, for someone who's flown one for ten years. Flying the RV-8 consumes a little more mental expenditure... more things going on and happening at a much quicker pace.
5 hours of flying in the RV-8 from Texas to Oshkosh is plenty enough in one day for me.
 
Last edited:
diamond said:
I'm talking about single legs, not multiple legs in 1 day.
Click to expand...

Then that pretty much limits to 2-4 hours for the kind of planes most of us fly here due to fuel capacity being the limit, not pilot fatigue. I once flew a 4.5 hour leg in the Cherokee and my concern for fuel was much greater than any fatigue. Even though calculating the fuel consumption said that I still had plenty left, and even after I landed, there was still almost an hour's worth left, when you're flying along with both gauges sitting on almost empty, that's pretty unnerving and made me feel like I was pushing my luck. I limited my maximum legs to 4.0 hours after that flight.
 
I said 4-5 hours in one leg, but that is with an autopilot. Two full tank legs in my -6A are the absolute limit.

That said, I have done glider flights of 7 hours +, for sure without an autopilot. Those have included oxygen above 5K, energy bars, lots of water, a working overboard dump system, and caffeine pills.

Bruce Patton
RV-6A
HP-18
RV-10 starting soon
 
I have done 5.5 hr legs in the ten with no real fatigue. What exhaust me out is making to many stops. Lots of work to get the kids in and out. An 8 hr flying day with one or two stops is much better than 3 or 4 stops. Stops just add to much time to the trip. Also getting beat up by ruff air can make the 8 hrs to much. Just to many factors to give a true time. Some days we traveled 12 hrs of the day from start up to shut down just to beat weather home. That is my over all max even if the weather is good.
 
Depends on conditions, in a day 9+ is possible in the RV 10. This could be 3 x 3 or 2 x 4.5 hour sectors.

In. -7 or -8 maybe 25% less due to the extra comfort and room.

Hydration and oxygen help, so lots of variables. A 2.5 hour trip in the -10 is easy :)
 
Alot of variables here, maybe too many to get answers which can lead to a conclusion.

One factor which will greatly influence the hours a person can fly, is if an autopilot is used or not.

There's ofcourse alot of other factors too, but handflying vs montoring, and for several hours in a row, is two very differnet ways to fly.
Maybe this poll schould reflect that?
 
Last edited:
True, in real IMC the AP is a great help single pilot. With two its great fun sharing the load.

In VMC I can be more fun to hand fly to keep you from becoming bored.
 
Smooth, see for ever, fly for every.
But:
I think it differs based on speed of the aircraft. In an RV you cover 500+ nm in 3 hours. In this US of A in 500 miles you are either entering a different weather pattern or terrain. For those of us that do not do enough cross country to justify in-air weather (yes, surprising there are still some of us), stopping every 500-600 nm to check ahead is not a bad idea, in my opinion.
 
Last edited:
There are definitely a lot of factors. So, the biggest variables that contribute to my threshold are:

  • I am not flying IFR these days (that can add and subtract since I need to deal to have lots of 'outs' when I see clouds I did not expect)
  • I now have an autopilot that works really well
  • I have a bladder solution - no comments on this one
  • I still wince every time I hear anything that sounds like a change in engine noise (I am way sensitive to this)

So ...

  • Without the AP, with clouds at lots of variable altitudes, and the tiniest unexpected vibration change from the engine = threshold is about 3 - 3.5 hours
  • With the AP, long range viability at altitude, and no 'surprises' = a 3 - 4 hour leg followed by a 3 hour leg.
 
Depends (not the diaper)

A few years back I touched down at all 109 public use airports in NC in one day. Logged over 17 hours of seat time and felt pretty rested after a burger and a beer at the end of the day.

I fly two 35 minute practice sessions with Team RV and I'm whooped! :eek:
 
Endurance

I claimed 6 to 7 hours, and that is in our 1976 Piper Lance. This is very airframe dependent for me. In the Pitts S-2A an hour can seem a long time. Haven't had the chance for any long flights in an RV; am guessing 3 hours might be about right in the RV-8. I'd like to hear what people taking a lot of trips in various RV's find a reasonable and comfortable flight duration. Thanks to all.
 
Well the question is strange given this qualification

diamond said:
I'm talking about single legs, not multiple legs in 1 day. Don't over think the question here. I know there are situations where long sustained turbulence can add fatigue, but I'm referring more to common and mostly comfortable weather conditions with periods of mild to moderate turbulence thrown in occasionaly. My poll also assumes auto pilot use if that is your normal mode of operation on long flights.
Click to expand...

I have never in my life had enough fuel to hit my fatigue limit. When I fly, I fly little, range limited airplanes to get somewhere and as Ron Lee discussed, that is the way we (apparently few) travelers are concerned about fatigue. When not racing I have 4 tanks on our RV-6A holding 55 gallons and I flight plan for 4 hours nominal at 75% power (or as close as I can get to it with altitude limiting effects) with a 1.2 hour reserve. Flying from Panama City to Fayetteville, Arkansas with an alternator failure (broken terminal) and battery turned off except for essential communication declared minimum fuel and landed with four reds because the float senders don't work that low. The kind of problems I have with fatigue come with a slow plane flying over totally boring desert like between Orange County, California and Bullhead, City, Arizona or flight days of 13 hours or so. 7 hours doesn't hardly make the bottom of my endurance and I'm 75. What is the actual point of the question? Are you concerned about having excessive fuel capacity that will limit you in some way and you want to minimize the margin? I guess I can understand that objective but it wasn't clear to me when I voted. When you ask me about flight fatigue I automatically think about how long I can fly before I have to stop and get some sleep. I checked in excess of 7 hours thinking that was what you wanted. Any thing else is going to be hard to quantify for me. Please disregard one 7+ hr vote.

Bob Axsom
 
Last edited:
You must log in or register to reply here.