Methods for altitude changes

> It depends on the situation, but for your specific example, of a 4 to
> 6 kft climb, I would increase power to max, then pitch (and trim) for
> about 90 kts. If I had the mixture leaned, I would go to full rich
> first (above 75% power, full rich is required for proper engine
> cooling). 90 kts is faster than Vy for my Cherokee (about 72-74 kts),
> but is recommended for cruise climb since it results in a lower nose
> and better forward visibility, and also better engine cooling.
>

For Mr Fly Cherokee.

A full rich climb at those altitudes can result in lower performance. If
your POH engine manual dictates full rich above 75% power.. then I cannot
recommend against following that procedure.

However, At 5Kft MSL, on a hot day at full throttle are you really getting
75% power? The Density Altitude.. ohh.. that bugger we live with in the
west.. could be well above 8Kft MSL. 5K Pressure Altitude, 30C, = 7779
Density Altitude

If you find that climbing through 5Kft MSL your RPMs are dropping off, then
lean to max RPM for max performance of the engine and then bump it rich just
a tad.

BT

> It depends on the situation, but for your specific example...

As a real student pilot (real as in, my feet leave the ground) I would
like to thank FlyCherokee and BT for their informative posts.

Guys, I do appreciate the frustration with Mxsmaniac, but I sometimes
think (having lurked in this group for a while) that you are all a
little too quick to show-off your razor-sharp wit in response to his/
her posts. If you are going to respond, why not do it productively?
Believe me, there are some of us here that do appreciate your
experience and insight. It is even interesting to see how the
experience of real flight conflicts with a simulated experience (the
obvious, of course, being the severity of a 'crash' :o))

I am certain that anyone with the brain power to safely operate an
aircraft, has the ability to keep on topic without being drawn into a
flamewar.... despite Mxsmaniacs 'crosswind' effect.

Thanks.

I merely wanted to speak about full rich full power climbs mentioned by Mr
Cherokee... many POH suggest leaning for max power take offs at high DA
airports... why should the DA airport make any difference than climbing at
high DA altitudes... you still want performance from the engine.. while
keeping the engine safe from overheating

I did not intend to answer MX

BT

<wesley.hall@> wrote in message
news:1176038172.073395.208870@y66g2000hsf. o...
>
>> It depends on the situation, but for your specific example...
>
> As a real student pilot (real as in, my feet leave the ground) I would
> like to thank FlyCherokee and BT for their informative posts.
>
> Guys, I do appreciate the frustration with Mxsmaniac, but I sometimes
> think (having lurked in this group for a while) that you are all a
> little too quick to show-off your razor-sharp wit in response to his/
> her posts. If you are going to respond, why not do it productively?
> Believe me, there are some of us here that do appreciate your
> experience and insight. It is even interesting to see how the
> experience of real flight conflicts with a simulated experience (the
> obvious, of course, being the severity of a 'crash' :o))
>
> I am certain that anyone with the brain power to safely operate an
> aircraft, has the ability to keep on topic without being drawn into a
> flamewar.... despite Mxsmaniacs 'crosswind' effect.
>
> Thanks.
>

Thanx Dave... now we wait for MXs inevitable counter replies.. I made the
error and got into many debates, if he does not get "his" answer.. he keeps
pushing and not accepting the advice of many with 30+yrs experience. I will
comment on other inputs.. but I will not answer MX.

It seems he is a walking... wait.. sitting wikepedia... on so many topics...
remember that wikepedia is written by less than average people with
something to say... yes there is knowledge there... not to discount
wikepedia.. but it is un moderated.

BT

"Dave" <mariners_nukethis@rogers.com> wrote in message
news:t5vh13lup233ibph80m07pkrn0n15qa1h0@...
> Well stated!
>
> Of all the above, 2 knew the answer and posted proper replies....
>
> Others could not wait to trumpet their attitude... (sigh)
>
> ..a lot of noise on this NG, and it is not from MX...
>
> Dave
>
>
>
>
>
> On 8 Apr 2007 06:16:12 -0700, wesley.hall@ wrote:
>
>>
>>> It depends on the situation, but for your specific example...
>>
>>As a real student pilot (real as in, my feet leave the ground) I would
>>like to thank FlyCherokee and BT for their informative posts.
>>
>>Guys, I do appreciate the frustration with Mxsmaniac, but I sometimes
>>think (having lurked in this group for a while) that you are all a
>>little too quick to show-off your razor-sharp wit in response to his/
>>her posts. If you are going to respond, why not do it productively?
>>Believe me, there are some of us here that do appreciate your
>>experience and insight. It is even interesting to see how the
>>experience of real flight conflicts with a simulated experience (the
>>obvious, of course, being the severity of a 'crash' :o))
>>
>>I am certain that anyone with the brain power to safely operate an
>>aircraft, has the ability to keep on topic without being drawn into a
>>flamewar.... despite Mxsmaniacs 'crosswind' effect.
>>
>>Thanks.
>

>> If you find that climbing through 5Kft MSL your RPMs are dropping off,
>> then
>> lean to max RPM for max performance of the engine and then bump it rich
>> just
>> a tad.
>>
>> BT
>
> Yes, you are quite right, density altitude is the key parameter. I
> have one of those ancient Cherokees with the pamphlet-style POH.
> There's not a lot in there, but they do say full rich over 75% power,
> which as I recall, is about 8 kft density altitude at full throttle.
>
> In any event, I've always been a bit conservative when it comes to
> leaning, I tend to err on the too-rich side, thinking that I'm helping
> the engine.
>

Mr Cherokee, I understand the problems with 1960-70s style POHs.
There have been some excellent articles in recent aviation magazines on
engine leaning, granted those procedures are best accomplished with added
engine monitoring instruments.

We fly a 1965 Piper Pawnee with 250HP (Lyc O-540) carbureted fixed pitch
configuration in glider towing operations. The airport is 2833MSL. Winter,
not many problems.. summer.. we are leaning as soon as we break ground for
max RPM. The mixture naturally gets richer as we climb after leaning due to
the climb, so we most always end up rich of peak and constantly monitor for
rpm drop with the richer mixture and then lean some more.

The mixture setting reached at altitude is left alone all the way back to
the ground.. lower power settings.. and is also used for ground idle if the
engine will idle without stumbling at that setting. Mixture is enriched for
go around or take off, until the engine gets up to speed and we are climbing
again. Oil temps are monitored, we do not have CHT or EGT gauges. Oil temp
in winter avgs about 180-190F, summer about 210F. We have two oil coolers
and change oil every 50hrs. We average about 250hrs per year on the engine
with weekend only operations.

BT

"Danny Deger" <dannydeger@m> wrote

> Good policy. Respond once and only once. And don't participate in the
> massive MX flaming that is the real source of this group getting plugged
> up with garbage. To you MX flammers out there -- please stop.

Once is once too much.

With the number of active posters in this group, if only half of them post,
that is too much ammunition to give him to argue with. Why answer at all,
when you know eventually, he will twist it and discount it _and_ the poster
is some manner. You KNOW he will. It is his constant.
--
Jim in NC

"Dave" <mariners_nukethis@rogers.com> wrote in message
news:t5vh13lup233ibph80m07pkrn0n15qa1h0@...
> Well stated!
>
> Of all the above, 2 knew the answer and posted proper replies....
>
> Others could not wait to trumpet their attitude... (sigh)
>
> ..a lot of noise on this NG, and it is not from MX...
>
> Dave
>
>
>
>
>
> On 8 Apr 2007 06:16:12 -0700, wesley.hall@ wrote:
>
>>
>>> It depends on the situation, but for your specific example...
>>
>>As a real student pilot (real as in, my feet leave the ground) I would
>>like to thank FlyCherokee and BT for their informative posts.
>>
>>Guys, I do appreciate the frustration with Mxsmaniac, but I sometimes
>>think (having lurked in this group for a while) that you are all a
>>little too quick to show-off your razor-sharp wit in response to his/
>>her posts. If you are going to respond, why not do it productively?
>>Believe me, there are some of us here that do appreciate your
>>experience and insight. It is even interesting to see how the
>>experience of real flight conflicts with a simulated experience (the
>>obvious, of course, being the severity of a 'crash' :o))
>>
>>I am certain that anyone with the brain power to safely operate an
>>aircraft, has the ability to keep on topic without being drawn into a
>>flamewar.... despite Mxsmaniacs 'crosswind' effect.
>>
>>Thanks.
>

I agree 100%. I have no problems reading his posts or ligit responses. It
is the contant flaming of MX that is clogging up this newsgroup. Let me
repeat this. It is the flaming of MX that is the problem here!!!

Danny Deger

> Thanks. I've visited that site before; the author becomes very abstract at
> times, but it is useful information.

Personally, as an engineer and generally 'theoretical' guy, I enjoy
the abstraction... but I understand what you're saying.

> By pitch climbing do you mean with the yoke, or with trim adjustments?

Yoke. Changing pitch attitude almost always induces phugoid
oscillations, with the yoke, those oscillations are trivial (almost
subconscious) to damp. Trim provides no such mechanism (without
grabbing the yoke anyways), so its generally a bad idea to fly with
it.

For any pitch attitude change, the general rule of thumb is pitch,
power, trim off pressure as necessary, in that order.

> If I have nose-down trim applied to go fast at my low altitude, it seems I
> should be able to trim slightly upwards and change altitude easily, then trim
> back for level flight at the new altitude. If I already have nose-up trim
> applied, this may not work, and eventually I'll have to add power.

It sounds like you're trying to fight the simulated phugoid
oscillation by using trim to make very low amplitude adjustments...
This just increases the period of the oscillations, it in no way
prevents them from occurring.

Power is a good, 'side effect free' mechanism of doing fine trimming
of your aircraft's altitude. In fact, I know instructors who advocate
only ever using the power to make the final 'lock' onto a new cruise
altitude, no matter what.

For example, the mechanism you would use to level off from a cruise
climb would be as follows:

500 feet below target altitude, push the nose forward gently to bring
airspeed up to cruise airspeed. Once you've reached cruise airspeed,
go ahead and trim to hold the attitude, but allow your power surplus
to continue pulling you up the last hundred feet or so to your target
altitude, only backing off the power the moment you reach it.

The descend-to-altitude is the same procedure, only with reduced power
instead (set up the aircraft in cruise attitude before you hit your
target altitude at a reduced descent power setting, and allow the
aircraft to settle onto target altitude before increasing power back
to cruise power)

I can see the theoretical advantages to this approach, but I would be
lying if I said I used to religiously (I still don't keep that far
ahead of the aircraft).

"EridanMan" <scott.cragg@> wrote in message
news:1176328741.004667.51380@y80g2000hsf. ...
snip

> Yoke. Changing pitch attitude almost always induces phugoid
> oscillations, with the yoke, those oscillations are trivial (almost
> subconscious) to damp. Trim provides no such mechanism (without
> grabbing the yoke anyways), so its generally a bad idea to fly with
> it.
>

You bring up a good point on phugoids. I have flown everything from J-3
cubs to F-4E (but no heavy time) and the difference in phugoid tendancy is
HUGE. On the Air Force jets, the trim in on the stick, so I didn't fly just
trim. I am currently flying a Taylorcraft which must have a highly damped
phugoid. I find I can fly it with only trim to make gradual changes in
altitude. In other planes, this can't be done as you mention.

Danny Deger

> For any pitch attitude change, the general rule of thumb is pitch,
> power, trim off pressure as necessary, in that order.
>
>> If I have nose-down trim applied to go fast at my low altitude, it seems
>> I
>> should be able to trim slightly upwards and change altitude easily, then
>> trim
>> back for level flight at the new altitude. If I already have nose-up
>> trim
>> applied, this may not work, and eventually I'll have to add power.
>
> It sounds like you're trying to fight the simulated phugoid
> oscillation by using trim to make very low amplitude adjustments...
> This just increases the period of the oscillations, it in no way
> prevents them from occurring.
>
> Power is a good, 'side effect free' mechanism of doing fine trimming
> of your aircraft's altitude. In fact, I know instructors who advocate
> only ever using the power to make the final 'lock' onto a new cruise
> altitude, no matter what.
>
> For example, the mechanism you would use to level off from a cruise
> climb would be as follows:
>
> 500 feet below target altitude, push the nose forward gently to bring
> airspeed up to cruise airspeed. Once you've reached cruise airspeed,
> go ahead and trim to hold the attitude, but allow your power surplus
> to continue pulling you up the last hundred feet or so to your target
> altitude, only backing off the power the moment you reach it.
>
> The descend-to-altitude is the same procedure, only with reduced power
> instead (set up the aircraft in cruise attitude before you hit your
> target altitude at a reduced descent power setting, and allow the
> aircraft to settle onto target altitude before increasing power back
> to cruise power)
>
> I can see the theoretical advantages to this approach, but I would be
> lying if I said I used to religiously (I still don't keep that far
> ahead of the aircraft).
>

> In a real airplane that burns real gas that costs real money, you climb
> to a cruise altitude that allows for all the terrain and stay there.

Hell, I dunno, I think in a real plane that burns real gas, his
inadvertent decision to toddle along at Vy would actually give him
pretty good gas milage;)

But yeah, I missed that bit.