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This is more due to power loading decay IMO. I've flown C150s, 152s and 172s at altitudes in excess in 10,000' (I live at 6000' MSL) and generally felt no difference in stall/ spin recovery at higher altitudes than I would a bit lower. Now when I visit friends who reside close to sea level and have an opportunity to fly with them, I notice the performance difference, especially on take off.I've got some time in a Victa Airtourer 100. When I did stalls for training, I was around 3,000 ft.
One day for giggles, my brother and I took it up to 10,000 ft. Due to its small wing area and 100 hp O-200, it has a rather poor climb rate. We got to 10,000 ft after a very long hour. ATC thought we were never going to make it.
Once we got their, we didn't know what to do - so with all the wisdom that a pair of teenagers could muster, we stalled it.
The stall was at the usual IAS, but bugger me it was different. Instead of the usual waffle and nose drop, it dropped a wing and despite almost instant full rudder to catch it - that wing kept going. It got past 90° very quickly. We eventually got right side up and wings level, but dropped a few thousand feet in the process.
Getting back to the question, any planes controls are less effective at altitude. The impact on the planes performance is likely related to the way wing loading and power loading decay with altitude.
I've got some time in a Victa Airtourer 100. When I did stalls for training, I was around 3,000 ft.
One day for giggles, my brother and I took it up to 10,000 ft. Due to its small wing area and 100 hp O-200, it has a rather poor climb rate. We got to 10,000 ft after a very long hour. ATC thought we were never going to make it.
Once we got their, we didn't know what to do - so with all the wisdom that a pair of teenagers could muster, we stalled it.
The stall was at the usual IAS, but bugger me it was different. Instead of the usual waffle and nose drop, it dropped a wing and despite almost instant full rudder to catch it - that wing kept going. It got past 90° very quickly. We eventually got right side up and wings level, but dropped a few thousand feet in the process.
Getting back to the question, any planes controls are less effective at altitude. The impact on the planes performance is likely related to the way wing loading and power loading decay with altitude.
But power loading is going to be the critical factor. In the example shown that 100 hp O-200 was probably only producing 60 HP at altitude, thus the reason for the poor climbRight, exactly. And planes with a higher wing loading and relatively poor power loading are going to have more problems like that at lower altitudes in hot weather, it seems to me.
49th Pursuit Group absorbed many survivors of the Phillipines and Java, skimmed the cream of the newly arrived replacement pilots, and early on, served in an air defense role in the Darwin area, flying a single type, armed with a single weapon type, thereby simplifying maintenance.
8th and 35th Pursuit Groups were equipped with a variety of models of Airacobra, P-400s, P-39D ( of different blocks), P-39F. These were armed with three different weapons, vastly complicating supply and maintenance requirements. Plus, their theater of operations, defending Port Moresby, and conducting offensive operations across the Owen Stanleys, was a much more challenging one. P-38 squadrons being stood up or converting from other types got to cherry pick the best and brightest veteran pilots.
But power loading is going to be the critical factor. In the example shown that 100 hp O-200 was probably only producing 60 HP at altitude, thus the reason for the poor climb
It is - but if you have power to keep airflow over the wings (regardless of the wing loading) you're going to stay airborne.Power loading is also affected by the DA right? I'll take your word for it about wing loading being a factor (or not) as well. Seems like it would make a difference but I'm not a pilot.
This is more due to power loading decay IMO. I've flown C150s, 152s and 172s at altitudes in excess in 10,000' (I live at 6000' MSL) and generally felt no difference in stall/ spin recovery at higher altitudes than I would a bit lower. Now when I visit friends who reside close to sea level and have an opportunity to fly with them, I notice the performance difference, especially on take off.
Pressure altitude is the height above a standard datum plane based on a barometric pressure. That's what you would adjust your altimeter to based on airfield pressure. With that known you can calculate your DAPressure altitude affects all aircraft the same, so it really isn't a factor. Unless there are clouds and mountains around. That's when things get "interesting".
Yes - because now you have a larger wing area to support the aircraft. Your lift coefficient will be higher. That's why gliders (and other aircraft) have long wings.Don't aircraft with larger wings handle better at high altitude? Isn't that why they had the HF and LF Spitfire, the former having the extended wing tips?
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Compared to a Victa Airtourer 100 possibly. The 150/ 152 has little dihedral so the stall is more abrupt and a wing tends to drop, but you want that in a trainer. The 172 stalls a bit cleanerCould that possibly be because Cessna 150-172 etc. have very good stall characteristics and a low wing loading?
To a point, again, how much air is being pushed over the wing? That's where the power factor comes into play.I get that it affects all aircraft equally, but (I guess I'm missing something here but I don't see it yet) it seems like an aircraft which was already kind of on the edge of being hard to control and / or 'twitchy' would have more trouble in the degraded (thin / hot air) conditions than one with a very good wing loading that was easy to handle.
Here's more on this;Don't aircraft with larger wings handle better at high altitude? Isn't that why they had the HF and LF Spitfire, the former having the extended wing tips?
View attachment 654739
Compared to a Victa Airtourer 100 possibly. The 150/ 152 has little dihedral so the stall is more abrupt and a wing tends to drop, but you want that in a trainer. The 172 stalls a bit cleaner
To a point, again, how much air is being pushed over the wing? That's where the power factor comes into play.
Yes - it is basically a trainer and designed that wayWhat I meant is, a Cessna (of any kind) has very benign stall characteristics and very low wing loading compared to a P-39 for sure right?
It will and again *Depending how much air is flowing over it*If the HF Spitfire had it's wing extended by 4 feet to improve handling in thin air, and the P-39 has a wingspan 5 feet shorter than an A6M2, 4 feet shorter than an F4F-3, and 3 feet shorter than a P-40, it stands to reason that at some altitude, the wing will play a role in higher altitude / more severe DA conditions. Ratios are similar vis a vis wing area and wing loading.
That's is dependent on the aircraft service ceilingThe question would then be at what altitude would that start to become noticeable or telling?
But it starts running out of power at around 15,000'Otherwise if it's just a matter of power to weight ratio, P-39 looks pretty good.
When I crewed at Reno, we had custom wingtips with a slight upward slope designed by some Scale Composites folks. They gave us better roll rates but we lost a few MPH. After flying one race and almost getting passed by another aircraft, we put the stock wingtips back.There was a difference in the wing tips. However sometimes it was subtle, at least at most altitudes. Like the clipped wingtip not showing much difference until around 20,000ft was reached? Although it improved roll. it is interesting because you should swap the set of tips back and forth if you wanted to. I beleive the Clip version gave you 231/2 sq ft, normal version gave 242 sq ft and the extended tip gave 248.5 so something else beside just wing area was going on. You were altering the aspect ratio of the wing and that can affect actual lift ratio of the whole wing.
Once you start comparing one wing and fuselage to another you had better know what you are doing.
Find the tests/reports for the Spitfires, unfortunately only they one compared two sets of tips at the same time.
There was a difference in the wing tips. However sometimes it was subtle, at least at most altitudes. Like the clipped wingtip not showing much difference until around 20,000ft was reached? Although it improved roll. it is interesting because you should swap the set of tips back and forth if you wanted to. I beleive the Clip version gave you 231/2 sq ft, normal version gave 242 sq ft and the extended tip gave 248.5 so something else beside just wing area was going on. You were altering the aspect ratio of the wing and that can affect actual lift ratio of the whole wing.
Once you start comparing one wing and fuselage to another you had better know what you are doing.