Sailplanes and VFR cruising altitudes

[N659HB]

Sailplane pilots: how does one maintain a VFR cruising altitude when flying from one thermal to another?

 

[Witmo]

Sailplane pilots: how does one maintain a VFR cruising altitude when flying from one thermal to another?

You don't.

 

[RotorDude]

The VFR cruising altitude rule only applies to aircraft not turning or climbing/descending while above 3000' agl, which rules out sailplanes 99% of the time.

 

[N659HB]

The VFR cruising altitude rule only applies to aircraft not turning or climbing/descending while above 3000' agl, which rules out sailplanes 99% of the time.

Thanks.

 

[Witmo]

The VFR cruising altitude rule only applies to aircraft not turning or climbing/descending while above 3000' agl, which rules out sailplanes 99% of the time.

Since when does turning obviate a proper cruising altitude above 3000? It may change based on the new track but it still applies. Sailplanes aren't ever required to maintain a cruise altitude, not even 1% of the time since they aren't powered.

 

[ZeroPapaGolf]

Since when does turning obviate a proper cruising altitude above 3000? It may change based on the new track but it still applies. Sailplanes aren't ever required to maintain a cruise altitude, not even 1% of the time since they aren't powered.

Did you read his link to 91.159?

 

[Witmo]

Did you read his link to 91.159?

I stand corrected. Since gliders are never in level cruising flight, they are not subject to maintaining an altitude.

 

[RotorDude]

I stand corrected. Since gliders are never in level cruising flight, they are not subject to maintaining an altitude.

That's only part of the 99%. The other two are: they are almost always turning, and often under 3000' agl (e.g. when ridge-running, where they could actually be fairly straight and level otherwise for significant stretches). The combination of these parts ends up being effectively excluded from the rule I linked.
And if you do read that link, you'll notice it says "or while turning". It does not exclude "lack of power".

 

[BillTIZ]

I stand corrected. Since gliders are never in level cruising flight, they are not subject to maintaining an altitude.

Well, we could be in level cruise in ridge lift (below 3000 AGL ) or wave (trying to stay below our max block altitude assigned). But we are at the whim of nature/weather to cruise or climb, so in most cases, it is beyound our control.

To answer the original OP, between thermal cruise, we are most likely descending while in search of that next thermal lift element.

 

[RotorDude]

Well, we could be in level cruise in ridge lift (below 3000 AGL ) or wave (trying to stay below our max block altitude assigned). But we are at the whim of nature/weather to cruise or climb, so in most cases, it is beyound our control.

To answer the original OP, between thermal cruise, we are most likely descending while in search of that next thermal lift element.

Yes, the only possible issue is with wave, where theoretically there could be a straight and level stretch, almost always above 3000' agl. But that's fairly uncommon, so would fall under the 1%. Bottom line: watch out for gliders!