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The PIREP says -47C on encounter (not -60C), beyond rime ice range but not impossible?

On CTAF no TWR in CAVOK, I can but no one around to take note, "cancel at xx:yy" In the other hand, contact or visual approaches are odd ones, few conditions need to be met at IF/FAF and ATC need to clear for it from there, it's unlikely that PIC can self switch to it half-way after ground in sight? These go horribly wrong by daylight in sunny blue sky at 2000ft agl, let alone at 100ft agl at night with low weather... https://www.aviation24.be/airlines/air-france-klm-group/air-france/twice-in-a-week-a-commercial-airline-approaches-for-landivisiau-naval-air-base-but-destination-is-brest-airport/

Aside from technicalities, it's an interesting question (especially with ground in-sight toward untowred airport under 700/1200 airspace) For 3D/2D short final: my understanding you can degrade from ILS min to LOC min on losing GP, you can degrade to LNAV from LPV (only above 1000ft agl?), you can pick CDFA or DnD profile...you don't need any ATC clearance for these, funnily, that may allow lower 2D minima than 3D, very uunusual but happens there is a pylon that kink into 3D DA survey surface but not 2D MDA survey surface, am I feeling lucky today? Near "airport area", my understanding you can't degrade from instrument circling into visual pattern: you are prohibited CTL without explicit ATC clearance even with ground in sight, 1/ if you having circling clearance you can't join visual pattern outside circling protection and 2/ you can't descend bellow CTL MDA without identifying non-ILS end threshold and being able to reach it with stable approach Now can one legally degrade GPS or ILS into IFR contact/visual or VFR join, I have no idea? in one hand, 91.175 does enforce being on the published standard procedure (even for Golf), also enforces approach weather minima to instrument runways even in non-towred airport...in the other hand, one can't decend bellow DA/MDA unless few conditions are met Let say you lose GPS, CAVOK day, short final LPV to untowred airport on CTAF frequency, can I fly using ground features? or I have to go missed and ask for another approach? There are likely other caveats regarding planning minima and missed procedure...

He was likely very low under 700ft agl flying in uncontrolled Golf airspace and going to non towered airport, why he would need ATC clearance for that flying? he was likely on CTAF frequency bellow radio/radar reception coverage: ATC tends to give up on anyone going low like that, on this occasion, they called for “low alert” but no answer… https://www.law.cornell.edu/cfr/text/14/91.173 If he was in controlled airspace with Approach (or final with Tower), he will need contact clearance but I highly doubt “IFR contact approaches” (ground in sight?) are allowed at night with ATC? what about “IFR visual approaches” (airport in sight?) at night with ATC? By day, 1 1/4 visibility & clear of clouds flying under 700ft/1200ft he could even call that (scud run) VFR: no clearance and no flight plan, by night, I would expect that would becomes 3nm visibility on higher ceiling minima? I gather this “ground contact business” tend requires more skills & luck than proper IFR on procedures to DA & MDA? life expectancy shrinks exponentially bellow DA & MDA on procedure at 0.5nm from runway let alone 3nm away on freestyle navigation, the most easy & obvious way to avoid ground & trees is to fly up away from them in clouds not go down to have a closer look The pilot likely saw the ground on short final, this happens often at night in marginal weather with layered clouds, that does not mean he should go for it? ground under with no runway ahead: run to hide into clouds !

It's ok to go under DA duing missed if you have official & protected vertical guidance: ILS, LPV, L/VNAV...no need to add +50ft to DA It's not OK go under non-procesion MDA: LOC, LNAV, CTL...even with advisory +V vertical guidance or CDFA, so most poeple add +50ft to MDA What one should not do is land after they decided to go missed near minimums: you often see runway during missed as the aircraft dips under "3D DA" and gets closed to threshold...not ideal for landing with bouncy doughnuts, you see the runway better on 2nd time

You are right, I just checked TERPS there are no differences in straight-out (3D) DA from Vref Category only turns or circling (2D) MDA, only difference in visibility requirement which account for the time one needs to acquire visual clues at DA, this also depends if you have AP, FD, HUD, EVS… In the other hand, I do recall some “extra design” requirements by FAA on speeds, - I recall FAA required +10% x ROD to MDA when calculating (derived) DDA for LNAV MDA flown on CDFA? this was done such aircraft never goes bellow MDA when executing missed…in ILS or APV(LPV or L/VNAV), you can go bellow DA as you go in missed even with -1000fpm as you stay above the protected glidepath, in LNAV or LOC, you should not dip under MDA - PDG climb gradient: a higher PDG require higher straight in DA during the missed, at higher climb speeds you get lower % gradient bracket with higher DA bracket, although this is for missed segment not final segment PANS-OPS have higher OCH/DH for higher Vref even in straight-in, so my comments likely come from another planet the physics are rather intuitive though: you see those runway lights better in slower aircraft, maybe better with AP coupled ILS or LPV with SV display and RHS looking outside with Cat-I/II xmas lights…

Cheyenne (91 or 135) can’t have lower minima than M20J on Part91 on that airport, they can only have higher ones !

1 1/4 for LPV (we don’t know minima for airplane with paying passengers, they are likely higher than system minima) in any case on same equipment & pilot, irrespective of airport plates & weather conditions and operational rules: * Cheyenne has visibility to approche => M20J has visibility to approche * M20J can’t see runway at DA => Cheyenne can’t see runway at DA * Cheyenne gone missed at DA => M20J can still land from DA I don’t see anything wrong in the above statements? As I said, I disagree that “M20J can’t approche behind Cheyenne, if the latter has gone missed”, I would just go and see myself

Sorry, I was using Jepps plates (these are produced for 121/135 criteria) with minima for Cat A & C aircraft (90kts & 120kias) both traffic were on remote altimeter setting which would beefed up visibility requirements and decision altitudes (FAA/Jepps plates ask for it) ATC gave Baltimore Altimeter to both aircraft, I have no clue what kind of operation (91/121/135) or equipments (BARO or WAAS) these aircraft have? what they were flying as minima (LPV, L/VNAV or LNAV)? what technique (3deg CDFA with autopilot or Dive & Drive to threshold by hand?)? but in all cases, 200ft overcast & 1 1/4 visibility will be a long shot Part91 with AP+LPV, why one would not give it a try in M20J and go missed at 350ft DH? I have no clue what minima those Cheyennes are operated on? the fact they have gone missed is a useful advisory information to adjust expectations but not the sole criteria out there start an approach, if I have enough fuel and LPV, I will personally give this one go down to DA and missed as well (or land if runway in sight) LNAV with no glideslope: dive-drive or circling, no thanks: it will be “run for my life” !

Why the Cheyenne crew went for it? the ceiling was definetly bellow their plates DA, the visbility was likely illegal at 120kias in their aircraft with paying passengers !! Likely they had few gadgets LPV, WAAS, AP, SV, HUD and maybe 2nd engine & pilot which is why they did it? What matters at the end of the day: they went missed as they did not like what they saw at DA !

It's November: aircraft sits with the mechanic, bad weather, end of year finances (plus I imagine in US nothing happens between TG & Xmas and that delicious turkey and happy family are gone ), so it's easy to reflect on one sad experience of GA ownership! We don't get many threads like this in July

I don't think Cheyenne going missed is a good reason? I am happy to proceed on those conditions in M20J for coupled LPV and 3D guidance but I won't hand-fly LNAV non-precision or circling with Dive & Drive in those conditions, I need 3sm & 600ft ceiling and some lights On Cat-I ILS (no Cat-II), you can land single piston when airliners are diverting due to deltas in DH and Vref, ATC may raise their eyebrows but you can have as much as 300ft ceiling advantage from slow speeds, obviously these are not the conditions for freestyle flying ! The minima are different for Cheyenne has 100kts with Vref > 90kts and would be higher than M20J with sub-90kts Vref but to be fair to your point the M20J clocked more than the Cheyenne on final segment On a side note, the pilot had the required visibility & cceiling to legally start up and depart (3sm & 400ft) and the required visibility (1 1/4sm) to legally approach on LPV, It's not very difficult to fly a coupled ILS or coupled LPV down to system minima, you legally have to go missed at your DA, even if you ignore by error (say wrong altimeter setting) or by choice (say minima does not apply to you) nothing bad happens: you will CFIT on runway touchdown point (runway/aircraft risks) not CFIT on pylons (huge 3rd party risks) The intersting bit here that the pilot was doing dive & drive on LPV which is a very new concept? unless he was flying LNAV non-precision or circling? but then he was way under his LNAV minima, bellow visual VDP and very optimistic about his skills I agree on the struggle to initiate the approach, if one pilot is going for 1sm visibility & 200ft ceiling, he should know every fix in his plate and every button in aircraft with executive decision at DA, especially at night & untowred airfield He had a freestyle start: can't find the IAF !!! and freestyle finish: turning an LPV 3D final into VFR in IMC scud run... It will be good to hear from the pilot one day, what equipment he had to be that comfortable going down (WAAS guidance? GS autopilot? SV display?) It can't be: I went LNAV in darkness, I saw some light between overcast ceiling gaps at 4nm, I pushed nose down and decided to fly cross-country "I Follow Roads & Lights" (IFRL) under OVC002, in FAA jargon, the (full actual) "contact approach"

That is the "right way" to do it In reality with 1sm visbility you tell ATC you are going to IAF ABCDE and let them organise traffic around you? if any traffic feel they are more than happy to go first with 1sm vis: be my guest, be first but please report ceiling on CTAF, I will come 2nd after... The last time I had this situation in France the guy behind me told me/ATC "he likes to hold and be number 2" and "I should go first, report ceiling and wish him go luck" I was in a school rented Archer2 with my gumpy wife no auto-pilot and rusty G430 (non-WAAS), he was in PC12 with comfy cow leather chairs fitted with AP, TCAS, TAWS, GPS-W, HUD or Synthetic-Vision and likely co-pilot !!! I reported the cloudbase after we vacated the active runway for him to land

That is a good point, it also removes IAF ROUAN from the flight plan and it's not in VTF straight line, so you can't just "eyeball it" when ATC ask you to go direct there, you have to intercept earlier and fly IF or FAF If you intercept tight or 2nm near FAF on VTF GPS approach is toasted: you don't get get glideslope and missed get removed, all you are flying is FAF-RWY leg with "approach not active" flashing As always, getting shortcuts in unfamiliar places and bad conditions give a headache while there is zero room for error or catch a falling knife, it does not hurt to take sometime to setup things...

I recall TAA in US is designed as operationally usable altitude and once you are cleared to IAF via feeder Area or Airway you can descend to TAA altitude: no one else will be under you going to that IAF and you won't hit terrain or get lost on radio/radar One can easily check in US plates that TAA altitude for GPS is never lower than Airway MEA or Radar MVA and way higher than conventional MSA (on exiting ILS or VOR fixes) This is not the case in many other countries (don't ask me how I know ) where TAA altitude are sometimes treated as MSA sector and GPS procedure are designed in standalone fashion and are not joined to feeder radar/airway routes: hence, you can't use it unless it's emergency and usually it's way under Airway MEA or Radar MVA, so that is the gotcha, also I recall FAA TERPS refer to TAArea while ICAO PANS-OPS use TAAltitude, this highlights how airport terminal GPS procedures are joined to the rest of the airspace structure and how conventional radar/airway routes mix with GPS routes (RNAV or RNP), it's a fiasco when you look how each country treat a descent to TAA or has implemented GPS procedures in exiting structures, many countries are allergic to direct IAF along the magenta with descent to TAA altitude, as it takes you off the ATC grid ! Maybe a bit of off topic and it's not YES/NO answer to the question but gives some color why you can do it in FAA land and why ATC expects you to do so, you always "remain in the ATC system"

From the video it seems that approach called him for "low alert" on procedure and he did not reply, maybe as he went into tower frequency? or was too low to receive ATC? A useful takeaway is to also keep monitoring radar approach frequency on COM2 when switching to untowred airports on COM1, the approach may keep monitoring the procedure on radar, if something was wrong if terms of situational awarness he could have caught it, gone missed and climbed to 3500ft !

I am worried he flew direct FAF (TIMBE), in the heat of the moment, if one does that on WAAS they don't get glide slope (official GS in LPV or advisory +V in LNAV+V) and they don't get the missed procedure at M/DA, they only fly FAF-RWY leg with "approach not active", on non-WAAS GPS you don't get APR annunciation but at least you know that you don't have glideslope and hopefully you are used to fly without one On this approach on these conditions, I won’t go down without LPV flashing and Gerorge (AP) holding the yoke for me ! I know ATC do give shortcuts to IF (BEGKA) or vector to 2nm before FAF on GPS but in these conditions of low visibility & ceiling, I think flying the whole approach from IAF (RUANE) is the safest bet, you just ask ATC direct "RUANE" and sit on it, no need to hurry up as there is not much traffic going on: fiddling with GPS approach with direct to FAF and 90deg intercept course is usually bad: unless one carefully monitors GPS messages, they only know about it when glidesslope fails (on GPS-W) or glitch when loading missed procedure at M/DA (on non-W GPS) I recall while ago getting direct to a point to start procedure that was not listed on my GPS as IAF or transition, I gently asked ATC to get direct ABCDE that I have active my GPS and briefed on plates already (one can activate legs, press here and there, check taa, open plates and re-breif...I was lazy and slightly behind aircraft on that one)

I agree 100%, I have set wrong QNH once on WAAS/SBAS LPV, you see the runway bellow your "real DA" other than that nothing fancy... However, wrong QNH on baro-LNAV/VNAV or pure LNAV (non-WAAS) is a different beast ! I am not familiar with US plates: if it was LNAV flying, the "V" ("VDP") at 1.4nm should matter? I recall it means 1:34 surface goes into something which is not ideal on wrong QNH at night or with 1+1/4SM visbility Is "V" a concern when flying LPV on 1:20 slope? should one avoid visually bellow DA? Also, is there a VISG/PAPI? and does it match LPV glidepath?

Looks like about the point where one legally disconnect his AP on LPV? it would be good to know if they had 3D guidance and if STEC AP does hook to LPV glide-slope? The weather minima are about the point where Walmart shop start to looks like Runway at night without 3D guidance… Looks terrifying to crash and hanging up there for hours, a miracle that they are alive and walked away !

He will be missed, such brilliant man and Mooney father ! RIP and condolences to his family

Should one bother with the propeller in the case of serious catastrophic engine failures? 90% of chances it's gone, or does not feather, or does not turn, or go to fine pitch by itself... I may feather it in glide (and go fine pitch for the flare) if it's something to do with air, fuel or mags though

Why 15 vs 23? is that KTAS vs KIAS conversion? or something specific to PA46? I don't recall best L-to-D ratio (or VSI to ASI ratio) does change a lot with altitudes? the air density rho will disappear from the ratio and it's pure alpha angle of attack and wing geometry...also, in gliders best ratio of VSI to ASI stay about the same all the way to 20kft, I have not flown higher than that but I don't think it will move a lot?

On the practical aspect, if you can’t get an appointment for the hypoxia chamber, I think it’s worth going up with someone else who can fly aircraft on oxygen on your behalf (instructor? or another pilot?), remove your own O2 in 16kft-24kft band for X minutes and fly by hand or autopilot down to 8kft I think this should give a better idea of personal symptoms and limitations? I am still waiting for an excuse or opportunity to go and try in Oklahoma but it’s a long way from France

In the meantime AA ordered 20 of these, they are not even built or certified yet ! https://news.aa.com/news/news-details/2022/American-Airlines-Announces-Agreement-to-Purchase-Boom-Supersonic-Overture-Aircraft-Places-Deposit-on-20-Overtures-FLT-08/

Why spoil a brilliant film with all these technicalities I think Hollywood forgot how to make action movies but Tom Cruise made a brilliant piece ! the film should have been 5h long of “pilot s**t”, 2h is not enough Next time when Sukhoi pulls the cobra in front of F14 nose, gun it: don’t say “what the f*** was that” that super manoeuvre is likely to sell fighters in airshows, in real life Cobra: 0 - 1: Missile