What's the maximum range of your plane?

Peter wrote:

So a descent, landing and a climb through hazardous / icing wx is a better option?

Maybe the thought is that if it’s that far an airline is easier?

If there is one available, maybe, but in most cases that option doesn’t exist other than one pre-planned some time before.

For example if you are planning a trip 5 days from now, you can get Easyjet tickets for 100 quid. If you leave the decision on airline v. GA till EOBT minus 24hrs you are looking at 500 quid and that is obviously per person.

The advantage of say 8hr endurance at 140kt is that if you have accurate fuel metering you can continue a flight to the planned destination, without the extra risk, cost and time wasted involved in an intermediate stop. Nobody likes an 8hr flight (well not unless you are with good friends and can have a good laugh) but it sure is a good solution to an unexpected headwind.

Flyer59 wrote:

LOP fuel flow: 9.9 GPH, TAS 160-162 Kts, Range (zero fuel): 1309-1325 NM (G2 model with 81 Gallons)

A G3 model with 92 Gallons could stay in the air 1486-1505 NM flown this way.

Alexis how did you calculate that?

Range is a thing where particularly marketing people have a lot of fun making funny figures which can lead to unscheduled glider experience.

But a good question. We should however agree to use similar calculations to compare properly.

This is how I´ve been instructed to do range calcs at the airline and how I do it today.

First, determine total fuel available. That is full fuel minus unusable.
Then deduct your final reserve, normally 45 minutes at the relevant cruise setting is the minimum, most people will want more.
That leaves the fuel available for the trip.

From that, you need to determine fuel and distance to climb and descent to the FL you are using. The fuel gets deducted, the distance added to the total range. If you want time as well, add those up.

That will leave you with the fuel available for cruise, which then can be divided through the relevant fuel flow.

For my plane, the optimum range FL is 100 with Long Range Cruise, 135 kt @ 7.8 GPH.
Total useable fuel is 52 USG.
Final Reserve would be 6 USG.
Remains 46 USG for the trip.
Fuel to climb is 2.5 USG, 20 NM and 13 Minutes.
Fuel to descend is 2.2 USG, 36 NM and 14 Minutes.
Leaves 41.3 USG for cruise. Divided by 7.8 GPH = 5.2 hrs @ 135 kts: 714 NM.
So the calculated range for this would be:
714NM + 56 NM = 770 NM
5:12 plus 13 + 14 minutes = 5:39 Endurance
Remaining fuel would be 6 USG.

At 75% power, fuel flow goes up to 10.8 GPH @ FL100, 3.8 hrs @ 150 kts = 573 NM + 56 = 629 NM.

Realistically, I´d plan up to 600 NM. Of course, any requirement for alternates e.t.c. will have to be deducted.

Theoretical range for my DA40 is 1083NM at 60% at FL100. 4,2 GPH, 40 USG tank, 115kt TAS. That’s 9,5 hours :)

Longest I’ve flown was about 630NM at 75% at FL100 in 4,5 hours. I used about 24 USG.

Neil wrote:

Maybe the thought is that if it’s that far an airline is easier?

I would certainly prefer a descent in IMC with the risk of some icing than that length of flight, yes. I think it is highly unusual for there to be no safe options in the middle 500nm of an 1100nm flight. Having extra range is great of course for a ferry or oceanic flight, but I like to break the journeys personally if I can.

I have calculated the maximum “beam-me-up-to-cruise-altitude-and-glide-down” range of our aircraft to:
Cessna 172b: 677NM / 7:46h (19 lph, 87KTAS, FL100, 2100RPM, 148 liters useable)
Jodel DR250/160: 831NM / 6:30h (31 lph, 128KTAS, 9840ft, 2500RPM, 200 liters useable)*
Morane MS883: 782NM / 8:30h (20 lph, 92KTAS, 8200ft, 2600RPM, 170 liters useable)
Morane MS894: 668NM / 5:39h (30 lph, 118KTAS, 1000ft, 2500RPM/760mb, 170 liters useable)
Bölkow BO208 Junior C: 502 NM / 5:58h (17 lph, 84KTAS, FL100, 2200RPM, 100 liters useable)

* I think there might be more economic power settings, but lacking a fuel flow gauge, I just kept to the values published in the manual

I’ve owned two Robin HR100s, one a 200B with a 200hp IO360 and the current one with a 285hp Cont Tiara. Both have absurdly large fuel tanks for such small planes at 450L, 120USG. It means I can plan for 6hr flights with full IFR reserves, that’s at 155kts FL100. The longest leg I’ve flown in the Tiara was Casablanca Anfa to Dole LFGJ, 1070nm in 6.5hrs, with 2 hrs fuel left on arrival. It’s nice never having to worry about fuel, unforecast extra strong headwinds are no problem. I once arrived after a 5hr flight only to discover that the runway was unavailable at destination, I needed customs so a diversion would have been a major PITA, so stayed in the hold at 100kt, I could have stayed there for 8 hours! Obviously I didn’t, the runway was available soon afterwards, but the whole thing was no sweat. So long range can also equal long endurance which can sometimes be just as useful.

One big disadvantage is maintenance on the bladder tanks. They like to be kept full for longest life but that is clearly impracticable, so the outer tanks tend to be kept less than half full, which means they start to leak. Another snag is that 325kgs of fuel held out on the wing really changes the handling of the plane, it becomes quite ponderous in response.

Tankering fuel is also good, especially from the UK with duty free fuel.

Grumman AA5B Tiger
191liters useable fuel, 120kts, 60% power, FF 35 lph for calculation, gives a realistic range of 500 NM or 5hrs which ever comes first. Remaining is of theoretical 15 liters. Actually it will be more depending how many sectors I have flown. Living in the middle of Germany, any place is not more than 2,5 hrs flighttime away.

Jetprop:-
Allowing for 21 gallons taxi and climb to FL270, zero wind range is 1166Nm @ 900 Lbs of torque 260Kts (TAS), 30.6 GPH and 1336Nm @ 600 lbs of torque 215Kts 22.5 GPH.

I also have the option of plugging in my ferry tank which holds 66 Gallons, so just under another 3 hours or 600Nm @ 600Lbs of torque.

My personal endurance is about 6 hours, before l want out… The aircraft can certainly outlast me.

E