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Are controllers permitted to waive the 250 below 10 restriction? Specifically a tower controller in class D? does it matter if its a military controller? I have heard a lot of opinions on this, looking for some place to back it up. Thanks
"Go State"
I'm not trying to be a smarta$$, but what aircraft are too heavy to slow to 250?
(d) If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed.
How about an MD-80? 747?
You do not have to put flaps out to follow the rule as indicated above. A heavy 737 can't slow to 200 and keep the flaps up, so you don't have to when flying under Class B. Just fly the minimum clean speed. An MD-80 taking off heavy will need about 260 knots clean maneuver speed. Only a dolt would leave the flaps out to comply with the 250 rule in that case.
No, they aren't. Only the administrator can do that. The tower controller can waive the 200 knot Class D restriction, but not the 250 below 10,000 restriction. 91.117 is quite explicit about this:
(a) Unless otherwise authorized by the Administrator, no person may operate an aircraft below 10,000 feet MSL at an indicated airspeed of more than 250 knots (288 m.p.h.).
(b) Unless otherwise authorized or required by ATC, no person may operate an aircraft at or below 2,500 feet above the surface within 4 nautical miles of the primary airport of a Class C or Class D airspace area at an indicated airspeed of more than 200 knots (230 mph.). This paragraph (b) does not apply to any operations within a Class B airspace area. Such operations shall comply with paragraph (a) of this section.
(c) No person may operate an aircraft in the airspace underlying a Class B airspace area designated for an airport or in a VFR corridor designated through such a Class B airspace area, at an indicated airspeed of more than 200 knots (230 mph).
(d) If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed.
Right? Right about what, controllers do not have the authority to allow you to exceed 250 below 10K, how many times does this subject have to be debated?yeah i figured i was right by brokeflyer
I don't fly the Whale, but I believe they occasionally need to operate at a higher speed on departure, the PIC has the authority to do this, see paragraph (d).By all means, be a smarta$$, that's just frigging ridiculous. Yes, any aircraft can slow to 200. Show me one that can't.
"Public use", (military) aircraft are exempt from the FARs. Compliance is usually built into their SOP, they don't get violated by the FAA, just "THE BOSS".Thanks for the info and ref to the reg's. Does anyone know if military controllers have 'permission' from the administrator to waive speed restrictions? much like the those restrictions are removed in MOA's/restricted areas and specific low level routes? thanks again.
"Public use", (military) aircraft are exempt from the FARs. Compliance is usually built into their SOP, they don't get violated by the FAA, just "THE BOSS".
PBR
The Department of Defense's (DoD's) Flight Information Publication General Planning GP said:"(Exemption to Federal Air Regulations 91.177 issued to DOD, May 18, 1978)-Operations below 10,000 feet Mean Sea Level at Indicated Air Speed in excess of 250 knots, in noncompliance with Federal Air Regulations 91.117 (a), are authorized for military aircraft, including Reserve and Air National Guard components, only under the following conditions:...
"g. If the airspeed required or recommended in the airplane flight manual to maintain safe maneuverability is greater than the maximum speed described in Federal Air regulations 91.117, the airplane may be operated at that speed."
We authorize heavies all the time to exceed the 250kt rule in Class B. Get a B747-400 to RJAA without doing a 280KT climb...good luck. We authorize it all day every day.
(d) If the minimum safe airspeed for any particular operation is greater than the maximum speed prescribed in this section, the aircraft may be operated at that minimum speed.
How about an MD-80? 747?
You do not have to put flaps out to follow the rule as indicated above. A heavy 737 can't slow to 200 and keep the flaps up, so you don't have to when flying under Class B. Just fly the minimum clean speed. An MD-80 taking off heavy will need about 260 knots clean maneuver speed. Only a dolt would leave the flaps out to comply with the 250 rule in that case.
Where do you get your numbers?
MD80 series (reference the -83 here) If you look at the charts, assuming MGTOW of 149,500#, using the 150,000# chart, 33 degress C at sea level, Altimeter 30.06, dry runway, no wind, Flaps 15
Here are your speeds:
V1: 143
VR: 147
V2: 154
Flap Retract: 169
Slat Retract: 202
Final Segment: 223
Clean Maneuver: 252
The airplane will fly just fine cleaned up at 250 and climb no problem. Once you hit 10k push the nose over for a 300-320kt climb.
I don't think the Maddog is like a true heavy that has to have the slats out up till around 280. Comming out of Charlotte, ATC has to cancel a 280 speed restriction.
As for the 250/10k rule, well... Been into North Dakota airports and had controllers tell us no speed restriction below 10,000, and this was on the descent. Ultimately, if this question went to court, I would think the PIC is required to adhere to FAR/AIM regardless of what ATC tells you. Just MHO.
I get my numbers from memory from over 4 years ago, so I'm not surprised if they aren't super accurate. I do remember that the clean maneuver speed was sometimes over 250 knots, so section d of the FAR's applied. The point is, you are allowed to fly 252 knots in your example.
Pretty good memory to be that closeOf course you would probably agree most aircraft of the MD80 size are pretty close in numbers?
I went back a read my post, and sorry if it sounded a$$holish. Didn't mean to come across like that. I was more though questioning if slat retract speed is say, 200 kts, and clean maneuver speed is say 250 kts, what is there to say that you couldn't fly at 230 kts. Not that you would, but can you?
I have performance charts for several aircraft I do not fly, and have never flown. So my experience with this is somewhat new.
If someone could explain why pilots want to fly at clean maneuvering speed (other than having to keep slats/flaps extended) maybe I could get a better understanding.
My experience has been limited to V2+20 flaps up, climb at 250/.65
Does any of this have to do with say exceeding 15 degrees bank flaps/slats retracted? Because of VSL?
Good discussion here I think.
Sorry MK you don't have the authority to waive this regulation, the PIC does by applying the reg.We authorize heavies all the time
Where do you get your numbers?
MD80 series (reference the -83 here) If you look at the charts, assuming MGTOW of 149,500#, using the 150,000# chart, 33 degress C at sea level, Altimeter 30.06, dry runway, no wind, Flaps 15
Here are your speeds:
V1: 143
VR: 147
V2: 154
Flap Retract: 169
Slat Retract: 202
Final Segment: 223
Clean Maneuver: 252
On the -80's the faster speeds down low after takeoff are typically in a -88 version with forward and aft aux tanks. With these, and loaded for LAX or SFO or SEA you'd approach 170,000 lbs for take-off, if I recall.